Ink jettable, uv-curable compositions

ABSTRACT

Ink jettable and UV-curable compositions include a reactive polymer comprising: (a1) at least 20 mol % of recurring units comprising pendant metal complexing water-solubilizing groups, and (b) at least 5 mol % of recurring units comprising a pendant group capable of crosslinking via [2+2] photocycloaddition. The compositions can optionally have a humectant, a dye or pigment colorant, an anionic or nonionic surfactant, a water-soluble or water-dispersible acrylic polymer, or a water-soluble or water-dispersible polyurethane. Such ink jettable and UV-curable compositions can include a complex of reducible metal ions or metal nanoparticles with the reactive polymer.

RELATED APPLICATIONS

Related subject matter is described and claimed in the followingcopending and commonly assigned patent applications:

U.S. Ser. No. ______ filed on even date herewith by Brust and Wyand andentitled “Articles Prepared Using Ink Jettable, UV-Curable Compositions”(Attorney Docket K002031/JLT);

U.S. Ser. No. ______ filed on even date herewith by Brust and Wyand andentitled “Methods for Using Ink Jettable, UV-Curable Compositions”(Attorney Docket K002032/JLT);

U.S. Ser. No. 14/661,235 filed Mar. 18, 2015 by Brust, Bennett, andFalkner;

U.S. Ser. No. 14/661,278 filed Mar. 18, 2015 by Brust and Wyand; and

U.S. Ser. No. 14/661,327 filed Mar. 18, 2015 by Brust and Wyand.

FIELD OF THE INVENTION

This invention relates to ink jettable and UV-curable compositions thatcan be used to provide ink jet images forming various patterns,articles, and methods. Such compositions include unique reactivepolymers that comprise pendant crosslinkable groups as well as pendanthydrophilic groups.

BACKGROUND OF THE INVENTION

While inkjet printing methods are well known for printing text andimages meant for viewing by the human visual system, the ability ofinkjet methods to produce patterns of functional fluids on a variety ofsubstrates affords the possibility of expanding the use of inkjetmethods into the creation of functional patterns such as electricalcircuits, sensors, or even antimicrobial coatings. However, the use ofinkjet methods for functional patterning presents a number of challengesrelated to the limitations of the ink jet printing hardware and theunique requirements needed for ejecting inks. For example, most inkjetprinting methods are limited to a single drop size of greater than about10 μm, and more typically of from 20 μm to 50 μm, thus limiting thelinewidth of a functional pattern to at least those dimensions orgreater to achieve robust performance. A variety of circuitry can bedesigned with large macroscopic linewidths that are well suited toinkjet printing and various methods of patterning could be combined tocover a wide range of linewidths.

Each type of ink jet ejection method places specific demands orlimitations on the ink jet ink composition that can greatly limit thechoice of materials used to formulate the ink jet ink composition.Continuous ink jetting requires the ink jet ink composition to be pumpedat high pressure through a recirculation system that can include the useof high shear pumping and filtration that can damage or destabilizedispersions of polymers, pigments, or other functional materials such asmetal nano-particles. Piezoelectric drop-on-demand (DOD) print heads areoften the most tolerant of a wide range of ink jet ink compositionformulations including non-aqueous, high viscosity, and evenheat-curable formulations. Unfortunately, they tend to be expensive tomanufacture and suffer from slower ink jet ejection rates. Thermal DODprint heads are relatively inexpensive to manufacture, offer a widerange of designs, and can be fired at ejection rates in excess of 30kHz, thus allowing the highest print speed for DOD printing. They alsorequire the ink jet ink composition to come into contact with aresistive heater that vaporizes enough ink jet ink composition to form avapor bubble capable of ejecting the remaining ink jet ink compositionin the chamber out through the nozzles such that the ejected droptypically has a velocity of about 10 m/sec or greater. The resistiveheating element typically reaches temperature of about 300° C. that candecompose or destabilize the ink jet ink composition and cause kogation(build-up of decomposition products on the heater surface or in the inkchamber) and eventual nozzle clogging or heater failure.

The need for efficient energy transfer from the resistive heater to theejected drop also favors aqueous-based inks due to the high vaporizationenergy of water, although non-aqueous thermal inks are known but rarelyused. All DOD ejection systems will tend to form a very fine mist due tothe formation of unwanted satellite drops. The use of organic solventsin ink jet ink compositions can create a serious health and safetyhazard due to this fine mist formation.

Ink jet ink compositions used for functional printing (that may includeelectroless metal plating) will often be designed to adhere to flexiblesubstrates such as polyesters like polyethylene terephthalate (PET) withgood adhesion and durability. Ink jet ink compositions that can behardened or cured using heat or radiation are well known and widely usedfor this purpose. They are often generically referred to as “UV-curableinks.” Such inks are typically formulated with vinyl monomers oroligomers that contain one or more pendant vinyl groups that canpolymerize and form a crosslinked network. The polymerization orcrosslinking is most often initiated by free radicals formed from anadded initiator compound that decomposes into active radicals uponexposure to appropriate wavelength UV-radiation or heat. UV curing mayoccur almost simultaneously with the printing, or it can be delayed.UV-curable inks are most commonly organic solvent-based and are ink jetprinted with piezo print heads to avoid the need for vaporization andthe possibility of premature polymerization in the print head fromthermal initiation by the high temperatures of the resistive heater of athermal print head. Some aqueous ink jet ink compositions have beenreported and contain water-soluble cross-linkable oligomers and freeradical initiators such as those commercially available as Sartomer®SR415 and Irgacure® 2959.

UV-curable ink jet ink compositions formulated with multi-functionalvinyl or acrylate monomers and UV-activated free radical initiators haveseveral drawbacks, especially if they are ejected with a thermalprinthead. The radical initiators, while triggered by UV light attemperatures typically below 100° C., will thermally decompose to formradicals at higher temperatures such as those near the 300° C. resistiveheater in a thermal ejector chamber. This can cause prematurepolymerization in the nozzle or ink-feed plenum resulting in ejectorplugging or failure and poor reliability. Secondly, the organic solventsand the vinyl monomers contained in the non-cured ink are flammable andoften unsafe for human exposure, especially as an extremely fine mistthat often accompanies most DOD printing. While some aqueousformulations are possible, the formulation options are limited due tolimited solubility of the components and even aqueous-based formulationscan still be hazardous because of the presence of acrylate monomers oroligomers known to cause toxic sensitization reactions on exposure.

Ink jet ink compositions useful for functional patterning to formcatalytic patterns useful for further chemical processes such aselectroless metal plating or sensor formation should be insoluble inaqueous solutions that are often strongly basic solutions after ink jetprinting, but they should remain permeable to water and other aqueousreactants such as metal ions or complexes and reducing agents.

Thus, a unique type of UV-curable polymer is needed to avoid all ofthese problems. Such UV-curable polymers should be very water-solublebefore crosslinking, but should become water-insoluble but still aqueouspermeable after crosslinking and after the ink jet ink compositions areprinted.

The UV-curable polymers should also have the capability to complex metalions and possibly stabilize the formation of metal nanoparticles bycontaining an adequate level of metal complexing functionality such ascarboxylic or carboxylate groups, sulfonic acid or sulfonate groups,phosphonic acid or phosphonate groups, and possibly other functionalitysuch as amide, alcohol, and amine groups. The crosslinking functionalityof these polymers should also be stable to the thermal ejection processduring ink jet printing and have typical long-term storage properties.

Aqueous UV-curable ink jet ink compositions that contain amulti-functional water-soluble acrylate monomers with free radicalphotoinitiators have been reported in U.S. Pat. No. 6,846,851(Nakhmanovich et al.) and U.S. Patent Application Publication2002/0198289 (Gummeson). This type of chemistry is also well known forthe preparation of hydrogels and interpenetrating networks that can beused to complex and form stable metal nanoparticles. Unfortunately,these types of ink jet ink compositions will likely exhibit thedrawbacks described above for UV-curable inks, especially when used forthermal print head ejection.

Thus, there is a need to address these problems with improved UV-curableink jet ink compositions.

SUMMARY OF THE INVENTION

The present invention provides an ink jettable and UV-curablecomposition comprising:

a reactive polymer comprising: (a1) at least 20 mol % of recurring unitscomprising pendant metal complexing water-solubilizing groups, (b) atleast 5 mol % of recurring units comprising a pendant group capable ofcrosslinking via [2+2] photocycloaddition, and optionally (c) at least 1mol % of recurring units comprising a pendant amide, hydroxyl, or lactamgroup, or a pendant precursor moiety for the pendant amide, hydroxyl, orlactam group, all amounts based on the total recurring units in thereactive polymer; and optionally, one or more of the followingcomponents:

a humectant,

a dye or pigment colorant,

an anionic or nonionic surfactant,

a water-soluble or water-dispersible acrylic polymer, and

a water-soluble or water-dispersible polyurethane.

In addition, the present invention further provides an ink jettable andUV-curable composition comprising:

a complex of reducible metal ions or metal nanoparticles with a reactivepolymer, the reactive polymer comprising: (a2) at least 5 mol % ofrecurring units comprising pendant sulfonate groups, (b) at least 5 mol% of recurring units comprising a pendant group capable of crosslinkingvia [2+2] photocycloaddition, and optionally (c) at least 1 mol % ofrecurring units comprising a pendant amide, hydroxyl, lactam group,carboxylic acid, phosphonic acid group or a pendant precursor moiety forthe pendant amide, hydroxyl, lactam, carboxylic acid, or phosphonic acidgroup, all amounts based on the total recurring units in the reactivepolymer; and

optionally, one or more of the following components:

a humectant,

a dye or pigment colorant,

an anionic or nonionic surfactant,

a water-soluble or water-dispersible acrylic polymer, and

a water-soluble or water-dispersible polyurethane.

An ink jettable and UV-curable composition is provided by the presentinvention, which composition comprises a water soluble, metal complexingpolymer that can be crosslinked or cured by exposure to UV-radiationthrough a [2+2] photocycloadditon process that does not require a freeradical initiator and is insensitive to thermal initiation during inkjet printing, making it well-suited for ejection using a thermal printhead. The ink jettable and UV-curable composition of this inventionoptionally contains one or more aqueous compatible humectants orsurfactants to improve ink jet drop formation and ejection reliability.The composition can also optionally contain additional water-soluble orwater-dispersible polymers such as an anionic polyurethane or anionicstyrene-acrylic copolymer that can further improve jetting performanceand durability of the ink jet printed image.

The, the advantages from the present invention are provided using aunique reactive polymer that is water-soluble or water-dispersible andcan be used to form a complex with either reducible metal ions (forexample, reducible silver ions) or metal nanoparticles (for example,silver nanoparticles). Two essential features are present in thereactive polymer to provide the desired properties. The first essentialfeature for some embodiments of the present invention is the presence ofgreater than about 5 mol % of (a2) recurring units comprising sulfonicacid or sulfonate groups. The second essential feature is the presenceof at least 5 mol % of (b) recurring units comprising a pendant groupcapable of crosslinking via [2+2] photocycloaddition group. A variety ofother recurring units can be present in the reactive polymer, forexample comprising pendant amide, hydroxyl, lactam, phosphonic acid, orcarboxylic acid groups to provide additional properties. Hydrophobicethylenically unsaturated polymerizable monomers such as styrene oracrylate esters can also be used in the polymerization processes toprovide polymers with enhanced film forming and durability.

The presence of the sulfonic acid or sulfonate groups in the reactivepolymers provides desired water solubility or water dispersibility for abroad range of uses, most importantly in the presence of reducible metalions that can precipitate other less water-soluble polymers. The pendantgroups that are capable of [2+2] photocycloaddition provide a built-incrosslinking function that is only activated by exposure to theappropriate UV radiation and is extremely thermally stable.

In other embodiments, the reactive polymers can comprise at least 40 mol% of the (a1) recurring units described herein that comprise pendantmetal complexing water-solubilizing groups along with the (b) recurringunits described herein.

The reducible metal ion or metal nanoparticle bearing polymericcomplexes used in this invention have a broad range of capabilities oruses due to the reactivity of the complexed reducible metal ions ormetal nanoparticles, high resolution patternability, andwater-solubility or swellability after reactive polymer crosslinking.These reducible metal ion or metal nanoparticle containing polymercomplexes can be ink jetted to form various ink jet printed images aswell as high resolution, electrically-conductive metal grid patternsbecause the metal nanoparticles can act as seed catalysts forelectroless metal plating. For example, these complexes can be ink jetprinted and exposed with a high resolution UV radiation and developed inwater before any further process such as electroless metal plating iscarried out.

These polymeric complexes containing reducible metal ions or metalnanoparticles can also be ink jet printed onto various surfaces (forexample, surfaces of various substrates described below) where they canbe hardened by UV-curing exposure or patterned with UV radiation to formmetal ion loaded crosslinked hydrogels (containing reacted polymers)wherein water and ions can readily diffuse in and out.

The reducible metal ion or metal nanoparticle containing ink jettableand UV-curable compositions described herein provide the opportunity tocombine both the inherent antimicrobial activity of certain metals (suchas silver and copper) with the advantages of the noted essentialreactive polymer features so that pattern formation is also enhanced,further improving the inhibition of microbial colonization and growth.

In addition, the UV radiation patternability and water-solubility of thenoted metal ion or metal nanoparticle containing ink jettable andUV-curable compositions facilitate patterning in a roll-to-rollmanufacturing system using simple water-bath processing at variousstages.

DETAILED DESCRIPTION OF THE INVENTION

The following discussion is directed to various embodiments of thepresent invention and while some embodiments can be desirable forspecific uses, the disclosed embodiments should not be interpreted orotherwise considered to limit the scope of the present invention, asclaimed below. In addition, one skilled in the art will understand thatthe following disclosure has broader application than is explicitlydescribed in the discussion of any embodiment.

DEFINITIONS

As used herein to define various components of the ink jettable andUV-curable compositions, unless otherwise indicated, the singular forms“a,” “an,” and “the” are intended to include one or more of thecomponents (that is, including plurality referents).

Each term that is not explicitly defined in the present application isto be understood to have a meaning that is commonly accepted by thoseskilled in the art. If the construction of a term would render itmeaningless or essentially meaningless in its context, the termdefinition should be taken from a standard dictionary.

The use of numerical values in the various ranges specified herein,unless otherwise expressly indicated otherwise, are considered to beapproximations as though the minimum and maximum values within thestated ranges were both preceded by the word “about.” In this manner,slight variations above and below the stated ranges can be used toachieve substantially the same results as the values within the ranges.In addition, the disclosure of these ranges is intended as a continuousrange including every value between the minimum and maximum values.

Unless otherwise indicated, the term “weight %” refers to the amount ofa component or material based on the total solids of a composition,formulation, or layer. Unless otherwise indicated, the percentages canbe the same for either a dry layer or pattern, or for the total solidsof the formulation or composition.

The term “homopolymer” is meant to refer to polymeric materials thathave the same repeating or recurring unit along a polymer backbone. Theterm “copolymer” refers to polymeric materials composed of two or moredifferent repeating or recurring units that are arranged in any order(randomly or otherwise) along the reactive polymer backbone.

For the reactive polymers used in the present invention, the recurringunits can be arranged randomly along the reactive polymer backbone, orthere can be blocks of recurring units that occur naturally during thepolymerization process.

Recurring units in the reactive polymers described herein can begenerally derived from the corresponding ethylenically unsaturatedpolymerizable monomers used in a polymerization process, whichethylenically unsaturated polymerizable monomers have the desiredfunctional and pendant groups.

Alternatively, desired pendant groups can be incorporated withinrecurring units after polymerization of ethylenically unsaturatedpolymerizable monomers by reaction with requisite precursor pendantgroups.

The term “polymerization” is used herein to mean the combining, forexample by covalent bonding, of a large number of smaller molecules,such as monomers, to form very large molecules, that is, macromoleculesor polymers. The monomers can be combined to form only linearmacromolecules or they can be combined to form three-dimensionalmacromolecules that are commonly referred to as crosslinked polymers.One type of polymerization that can be carried out in the practice ofthis invention is free radical polymerization when free radical reactiveethylenically unsaturated polymerizable monomers and suitable freeradical generating initiators are present.

The term “reactive polymer” is used herein to refer to the copolymersdescribed below that have the described essential components andproperties and can be used in the compositions, articles, and methodsdescribed herein, and which copolymers are sensitive to ultravioletradiation so that crosslinking occurs using the pendant groups in the(a1) and (a2) recurring units noted below.

In reference to reactive polymers described herein, the term“water-soluble” is used to mean that the minimum solubility in water ofa given reactive polymer is at least 0.1 weight % at 25° C. Somereactive polymers can be less water-solubility but stillwater-dispersible. The term “water-insoluble” is used to mean that agiven reactive polymer is less than less than 0.1 weight % at 25° C.

The term “crosslinked reacted polymer” is used herein to refer to thecrosslinked form of the corresponding reactive polymer.

The term “aqueous-based” refers to solutions, baths, or dispersions inwhich the predominant solvent, or at least 50 weight % of the solvents,is water.

Unless otherwise indicated, the term “mol %” when used in reference torecurring units in reactive polymers, refers to either the nominal(theoretical) amount of a recurring unit based on the molecular weightof ethylenically unsaturated polymerizable monomer used in thepolymerization process or to the actual amount of recurring unit in theresulting reactive polymer as determined using suitable analyticaltechniques and equipment.

Unless otherwise indicated, the term “group” particularly when used todefine a substituent of a defined moiety, can itself be substituted orunsubstituted (for example and alkyl group” refers to a substituted orunsubstituted alkyl). Generally, unless otherwise specifically stated,substituents on any “groups” referenced herein or where something isstated to be possibly substituted, include the possibility of anygroups, whether substituted or unsubstituted, which do not destroyproperties necessary for the utility of the component or aqueous metalcatalytic composition. It will also be understood for this applicationthat reference to a compound of a particular general structure includesthose compounds of other more specific formula that fall within thegeneral structural definition. Examples of substituents on any of thementioned groups can include known substituents such as: halogen (forexample, chloro, fluoro, bromo, and iodo); nitro; cyano; amino; alkoxyparticularly those with 1 to 12 carbon atoms (for example, methoxy andethoxy); substituted or unsubstituted alkyl groups, particularly loweralkyl groups (for example, methyl and trifluoromethyl); alkenyl orthioalkyl (for example, methylthio and ethylthio), particularly eitherof those with 1 to 12 carbon atoms; substituted and unsubstituted aryl,particularly those having from 6 to 20 carbon atoms in the aromatic ring(for example, phenyl); and substituted or unsubstituted heteroaryl,particularly those having a 5- or 6-membered ring containing 1 to 3heteroatoms selected from N, O, S or Se (for example, pyridyl, thienyl,furyl, pyrrolyl, and their corresponding benzo and naptho analogs); andother substituents that would be readily apparent in the art. Alkylsubstituents particularly contain 1 to 12 carbon atoms and specificallyinclude “lower alkyl” that is having from 1 to 6 carbon atoms, forexample, methyl, ethyl, and t-butyl. Further, with regard to any alkylgroup, alkylene group or alkenyl group, it will be understood that thesecan be branched or unbranched and include ring (cyclic) structures.

The term “UV radiation” is used herein to refer to electromagneticradiation having a wavelength (λ_(max)) of at least 150 nm and up to andincluding 450 nm.

As used herein, all molecular weights are weight average molecularweights (M_(w)) that can be determined using known procedures andequipment if the values are not already known from the literature. Forexample, M_(w) can be determined using Size Exclusion Chromatography(SEC) and values are reported herein as poly(methyl methacrylate)equivalent weights.

In defining various dimensions of features and nanoparticles, eachdimension “average” is determined from at least 2 measurements of thespecific dimension using appropriate measurement techniques andequipment that would be known to one skilled in the art. For example,the average dry thickness of layers described herein can be determinedfrom the average of at least 2 separate measurements taken of a drylayer, for example, using electron microscopy. Similarly, the averagedry thickness or width of lines, grid lines, or other pattern featuresdescribed herein can be the average of at least 2 separate measurementstaken, for example, using electron microscopy. The “average diameter” ofsilver nanoparticles can be determined by at least two measurementsusing light scattering or electron microscopy, such as transmissionelectron microscopy (“TEM”).

The term “aspect ratio” is used to define the morphology of particlesincluding the silver nanoparticles described herein. The term has thewell understood meaning of the ratio of the largest dimension to thesmallest dimensions of an anisotropic particle such as a platelet orrod. In some embodiments of the present invention, the metalnanoparticles (such as silver nanoparticles) used in metal-containing(such as silver-containing) embodiments of compositions (B) and (D)described below is less than 2, or even less than 1.5 and such metalparticles are generally considered to be low aspect ratio ornear-spherical in morphology. In some embodiments, the silvernanoparticles in silver-containing embodiments of compositions (B) and(D) have an aspect ratio of greater than or equal to 2 and haveplate-like or platelet morphology.

In many embodiments of substrates and articles described herein, thetransparent substrate and all accompanying layers or features on one orboth supporting sides, are considered transparent meaning that itsintegrated transmittance over the noted visible region of theelectromagnetic spectrum (for example from 410 nm to 700 nm) is 70% ormore, or more likely at least 80% or even 90% or more, as measured forexample using a spectrophotometer and known techniques.

Unless otherwise indicated herein, the term “metallic” refers tomaterials that are single pure metals, metal alloys, metallic oxides,metallic sulfides, and materials containing metallic particles such asmicro-particles, nanoparticles, or grains.

Uses

The compositions, articles, and methods described or claimed hereininclude the use of reactive polymers and humectants in ink jettable andUV-curable compositions that can also contain water-soluble complexescontaining either reducible metal ions or reduced metal nanoparticles.The resulting water-soluble complexes have a variety of applicationsafter they have been formed.

In some embodiments, the water-soluble complexes containing the reactivepolymers can be ink jet printed onto various substrates in a patternedmanner for further chemical reactions such as providing catalytic silveror palladium nanoparticles that can then be used to form high resolutionelectrically-conductive metal patterns as described herein. Suchelectrically-conductive metal patterns can be incorporated into variousdevices including but not limited to touch screens or other displaydevices that can be used in numerous industrial, consumer, andcommercial products. Thus, the water-soluble complexes can beincorporated into silver-containing compositions described below whereefficient photopolymerization and metal pattern formation is needed invarious articles or devices.

Touch screen technology can comprise different touch sensorconfigurations including capacitive and resistive touch sensors.Capacitive touch sensors can be used in electronic devices withtouch-sensitive features. These electronic devices can include but arenot limited to, televisions, monitors, and projectors that can beadapted to display images including text, graphics, video images,movies, still images, and presentations. The image devices that can beused for these display devices that can include cathode ray tubes (CRT),projectors, flat panel liquid crystal displays (LCD), light emittingdiode (LED) systems, organic light emitting diode (OLED) systems, plasmasystems, electroluminescent displays (ELD), and field emission displays(FED). For example, the present invention can be used to formingelectrodes and peripheral electronic leads in thin film printedbatteries or photovoltaic devices.

Systems and methods of fabricating flexible and optically complianttouch sensors, batteries, or other printed electronics in a high-volumeroll-to-roll manufacturing process wherein micro electrically-conductivefeatures can be created in a single pass are possible using the presentinvention. The water-soluble silver-containing compositions can be usedin such systems and methods with multiple ink jet printers to formmultiple high resolution electrically-conductive images frompredetermined designs of patterns provided in those multiple ink jetprinters. Multiple patterns can be ink jet printed on one or both sidesof a substrate. For example, one predetermined pattern can be ink jetprinted on one side of the substrate and a different predeterminedpattern can be ink jet printed on the opposing side of the substratethat can be a continuous web.

In other embodiments, the present invention can be used to providesilver-containing articles that can be used for anti-fouling orantimicrobial purposes in various uses such as in aquatic or marineenvironments, or in clothing or medical devices.

Ink Jettable and UV-Curable Compositions

The ink jettable and UV-curable compositions of this invention containonly one essential component: one or more reactive polymers as describedbelow (besides a necessary aqueous medium such as water), and one ormore optional components such as humectants, surfactants, andwater-soluble or water-dispersible polymers as described below. Thesingle essential component is the only one needed for forming an inkjettable and UV-curable composition but as noted below, the optionalcomponents can be added to improve various properties including,dispersibility, manufacturability, printability, ink jetted imageevaluation, storage stability, or other properties.

Reactive Polymers

In general, the reactive polymers useful in the practice of thisinvention have two essential features. They comprise pendant groups thatare capable of crosslinking via [2+2] photocycloaddition (defined below)upon exposure to suitable radiation (usually UV radiation). In addition,the reactive polymers also comprise pendant metal complexingwater-solubilizing groups such as pendant sulfonate or sulfonic acidgroups or carboxylic acid or carboxylate groups that provide sufficientwater-solubility or water-dispersibility as well as metal complexationproperties. While the reactive polymers can be supplied as aqueous-basedcompositions, they can also be used when complexed with either reduciblemetal ions (for example, reducible silver ions, copper ions, orpalladium ions) or metal nanoparticles (for example, silvernanoparticles, copper nanoparticles, or palladium nanoparticles) asdescribed below on a substrate that can have a large or small surface,including the outer surfaces of inorganic or organic particles and thendried. Thus, the reactive polymers are reducible metal ion or metalcomplexing (as described below), water-soluble, and UV-curable orphotocrosslinkable.

The reactive polymers can be either condensation or vinyl polymers aslong as the requisite pendant crosslinkable and water-solubilizinggroups are connected to and arranged along the reactive polymerbackbone. In most embodiments, the useful reactive polymers are vinylpolymers derived from appropriately selected ethylenically unsaturatedpolymerizable monomers using known free radical solution polymerizationtechniques and conditions, initiators, surfactants, catalysts, andsolvents, all of which would be readily apparent to one skilled in theart from the teaching provided herein.

(a1) Recurring Units Having Metal Complexing Water-Solubilizing Groups:

Some embodiments of the reactive polymers useful in the presentinvention comprise (a1) recurring units comprising pendant metalcomplexing water-solubilizing groups that can include but are notlimited to, pendant sulfonic acid and sulfonate groups as well aspendant carboxylic acid groups, pendant carboxylate groups, pendantphosphonic acid groups, and pendant phosphonate groups. Such recurringunits can be provided by polymerization of suitable ethylenicallyunsaturated polymerizable monomers containing such metal complexingwater-solubilizing groups such as acrylic acid, methacrylic acid, vinylphosphonic acid, vinyl phosphonate, itaconic acid, maleic anhydride,maleic acid, fumaric acid, citraconic acid, vinyl benzoic acid,2-carboxyethyl acrylate, 2-carboxyethyl methacrylate as well as theethylenically unsaturated polymerizable monomers described below for the(a2) recurring units. Partially or fully neutralized counterparts ofsuch ethylenically unsaturated polymerizable monomers are also oftenreadily available and useful for certain polymer synthetic conditions.

Alternatively, such recurring units can be provided by polymerizingcertain precursor ethylenically unsaturated polymerizable monomers thatcomprise pendant precursor groups that can in turn be reacted to providethe desired pendant metal complexing water-solubilizing groups.

The (a1) recurring units described above having the pendant metalcomplexing water-solubilizing groups are present in the reactivepolymers in an amount of at least 40 mol %, or even at least 40 mol %,and up to and including 80 mol % or up to and including 95 mol %, allamounts based on the total recurring units in the reactive polymer.

(a2) Recurring Units Having Sulfonate or Sulfonic Acid Groups:

Other embodiments of the reactive polymers useful in the presentinvention comprise (a2) recurring units comprising pendant sulfonategroups and pendant sulfonic acid groups, or mixtures of both pendantsulfonic acid and pendant sulfonate groups. Such (a2) recurring unitscan be provided by polymerization of suitable ethylenically unsaturatedpolymerizable monomers containing such water-solubilizing groups such asvinyl sulfonic acid, styrene sulfonic acid,2-acrylamido-2-methyl-1-propane sulfonic acid, 2-sulfoethylmethacrylate, 3-sulfopropyl methacrylate, styrene sulfonates, and3-sulfopropyl acrylate. Partially or fully neutralized counterparts ofsuch monomers are also often readily available and useful for certainpolymer synthetic conditions.

Alternatively, such recurring units can be provided by polymerizingcertain precursor ethylenically unsaturated polymerizable monomers thatcomprise pendant precursor groups that can in turn be reacted to providethe desired pendant sulfonic acid or pendant sulfonate groups. Forexample, such monomers include but are not limited to, hydroxy oramino-containing compounds such as 2-hydroxyethyl acrylate,2-hydroxyethyl methacrylate, 2-aminoethyl methacrylate, and 2-aminoethylacrylate that can be reacted using a variety of sulfonating agents toprovide the desired pendant sulfonic acid or pendant sulfonate groups.

The (a2) recurring units described above having the pendant sulfonicacid or pendant sulfonate groups are present in the reactive polymers inan amount of at least 5 mol % and up to and including 80 mol % or up toand including 95 mol %, all amounts based on the total recurring unitsin the reactive polymer.

Crosslinkable (b) Recurring Units:

The reactive polymers used in the present invention also comprise (b)recurring units comprising a pendant group capable of crosslinking via[2+2] photocycloaddition when appropriately exposed to suitableradiation. While not limited to the following examples, suchphotosensitive crosslinkable groups can be chosen from one or more ofthe following classes of photosensitive crosslinkable groups, all ofwhich can be connected to a recurring unit backbone that is derived fromsuitable ethylenically unsaturated polymerizable monomers:

(i) a photosensitive —C(═O)—CR═CR¹—Y group wherein R and R¹ areindependently hydrogen or an alkyl group having 1 to 7 carbon atoms, a5- to 6-membered cycloalkyl group, an alkoxy group having 1 to 7 carbonatoms, a phenyl group, or a phenoxy group, and Y is an aryl orheteroaryl group;

(ii) a photosensitive, non-aromatic unsaturated carbocyclic group;

(iii) a photosensitive, non-aromatic heterocyclic group comprising acarbon-carbon double bond that is conjugated with an electronwithdrawing group;

(iv) a photosensitive non-aromatic unsaturated heterocyclic groupcomprising one or more amide groups that are conjugated with acarbon-carbon double bond, which photosensitive non-aromatic unsaturatedheterocyclic group is linked to the water-soluble backbone at an amidenitrogen atom, or

(v) a photosensitive substituted or unsubstituted 1,2-diarylethylenegroup.

Multiple photosensitive crosslinkable groups can be present from thesame or multiple different classes of the crosslinkable groups (i)through (v).

Upon exposure to suitable radiation having a max of at least 150 nm andup to and including 700 nm, or more likely exposure to radiation havinga λ_(max) of at least 150 nm and up to and including 450 nm, the notedphotosensitive crosslinkable groups are electronically excited such thatthey can react with other pendant groups in the reactive polymer to formcrosslinks for example as the product of [2+2] photocycloadditionreactions.

The reactive polymers particularly become crosslinked among adjacent orproximate (molecularly near enough for [2+2] photocycloadditioncrosslinking) crosslinkable groups during or after the notedirradiation. Thus, essential crosslinking can be accomplished using thereactive polymer without additional crosslinking agents. However, ifdesired, crosslinking can be further provided or enhanced using distinctcompounds that are dispersed as crosslinking agents within thecompositions or layers comprising one or more reactive polymers. Suchcrosslinking agents react at either the crosslinkable groups or at otherpendant groups such as pendant carboxylic acid groups or epoxy groupsdepending upon the chemical structure of crosslinking agent. For thependant crosslinkable groups described herein, crosslinking is achievedby having at least two of such crosslinkable groups in proximity thatcan react with one another.

The crosslinkable [2+2] photocycloaddition groups incorporated into thereactive polymers can absorb photoexposing radiation as described aboveto form an electronically excited state that can undergo pericyclic ringformation to form stable covalent crosslinks. These crosslinks betweenthe polymer chains cause the reactive polymer to become water-insoluble,although the water-insoluble reacted polymer can still absorb andtransport water, ions, or other small molecules. The photoexposingradiation can be followed by additional curing or heating procedures(described below) to allow the excited [2+2] photocycloaddition groupsto properly align with non-excited [2+2] photocycloaddition groups toform additional crosslinks. Curing can be shortened with highertemperatures.

The crosslinked, water-insoluble complex containing the crosslinked,water-insoluble reacted polymer can be crosslinked at a level thatimparts water-insolubility and adhesion to a substrate, but still allowsrapid diffusion of water, metal ions, and other small molecules. Thistype of water-compatible composition is sometimes referred to as ahydrogel. The diffusivity of the complex of crosslinked reacted polymercontaining either reducible metal ions or metal nanoparticles can becontrolled by designing the level of crosslinking and the addition ofhydrophobic recurring units such as the (c) and (d) recurring unitsdescribed below.

The (b) recurring units comprising the noted photosensitivecrosslinkable [2+2] photocycloaddition groups can be present in thereactive polymers in an amount of at least 5 mol % or typically of atleast 5 mol % and up to and including 50 mol %, or even of at least 10mol % and up to and including mol %, all amounts based on the totalrecurring units in the reactive polymer.

In the (i) class of pendant photosensitive, crosslinkable groups thatcan be present in recurring units arranged along the reactive polymerbackbone can comprise —C(═O)—CR═CR¹—Y groups wherein R, R¹, and Y aredefined as follows.

Specifically, R and R¹ can be independently hydrogen or substituted orunsubstituted alkyl groups having at least 1 to 7 carbon atoms(including substituted or unsubstituted methyl, ethyl, isopropyl,t-butyl, hexyl, and benzyl groups, and others that would be readilyapparent to one skilled in the art), substituted or unsubstitutedcycloalkyl group having 5 or 6 carbon atoms in the ring (such ascyclopentyl, cyclohexyl, 4-methylcyclohexyl, and others that would bereadily apparent to one skilled in the art), substituted orunsubstituted phenyl groups (such as phenyl, tolyl, and xylyl groups,and others that would be readily apparent to one skilled in the art),substituted or unsubstituted alkoxy groups having 1 to 7 carbon atoms(such as methoxy, ethoxy, benzoxy, and others readily apparent to oneskilled in the art), or substituted or unsubstituted phenoxy groups(such as phenoxy, 2,4-dimethylphenoxy, and others that would be readilyapparent to one skilled in the art). In some embodiments, R and R¹ canalso be nitro, cyano, or halogen groups.

More particularly, R and R¹ can be independently hydrogen or substitutedor unsubstituted methyl, ethyl or phenyl groups, especially when Y is asubstituted or unsubstituted phenyl group as described below.

Y can be a substituted or unsubstituted carbocyclic aryl group, or asubstituted or unsubstituted heteroaryl group having one or moreheteroatoms (oxygen, sulfur, or nitrogen) and sufficient carbon atoms tocomplete an aromatic heterocyclic ring. Such aromatic rings can have oneor more substituents that do not adversely affect the desired behaviorin the crosslinking reactions induced by the irradiation describedherein.

Useful Y groups can be either heterocyclic or carbocyclic rings havingdesired aromaticity and any of these rings can be substituted with oneor more substituents that do not adversely affect the function of thereactive polymer. Representative aromatic Y groups include but are notlimited to, substituted or unsubstituted phenyl, naphthyl, anthracyl,4-nitrophenyl, 2,4-dichlorophenyl, 4-ethylphenyl, tolyl,4-dodecylphenyl, 2-nitro-3-chlorophenyl, 4-methoxyphenyl, 2-furyl,2-thienyl, 3-indolyl, and 3-pyridyl rings. The substituted orunsubstituted phenyl rings are particularly useful including but notlimited to phenyl, tolyl, xylyl, 4-methoxyphenyl, hydroxyphenyl, andchlorophenyl groups. Substituted or unsubstituted phenyl or 3-pyridylgroups are particularly useful Y groups.

The pendant groups comprising the crosslinkable and photosensitive—C(═O)—CR═CR¹—Y groups are therefore connected to the reactive polymerbackbone by means of a single connecting bond or a linking group (R²) asdescribed below.

In particular, the essential recurring units comprising the notedcrosslinkable groups can be derived from any ethylenically unsaturatedpolymerizable monomer having appropriate pendant groups comprising oneor more crosslinkable —C(═O)—CR═CR¹—Y groups wherein R, R¹, and Y are asdefined above.

More particularly, such (b) recurring units can be further defined inreference to the following Structure (-A_(i)-) comprising crosslinkablegroups:

In Structure (-A_(i)-), R, R¹, and Y are as defined above. R² can be adivalent linking group including but not limited to, substituted orunsubstituted alkylene (including haloalkylenes and cyanoalkylenes),alkyleneoxy, alkoxyalkylene, iminoalkylene, cycloalkylene, aralkylene,cycloalkylene-alkylene, and aryloxyalkylene groups wherein the divalenthydrocarbon groups can comprise 1 to 20 carbon atoms (in either linear,branched, or cyclic form). A skilled worker in polymer chemistry wouldbe able to design other useful linking groups using suitable number ofcarbon and hetero (oxygen, nitrogen, or sulfur) atoms in an order andarrangement that are chemically possible. Particularly useful R²divalent groups are substituted or unsubstituted alkylene groups such assubstituted or unsubstituted ethylene or propylenes.

R³, R⁴, and R⁵ can be independently hydrogen, a halogen, a substitutedor unsubstituted alkyl group having 1 to 6 carbon atoms, a substitutedor unsubstituted cyclohexyl group, or a substituted or unsubstitutedphenyl group.

In particular, R³, R⁴, and R⁵ can be independently hydrogen, chloro,methyl, or ethyl groups.

Some particularly useful ethylenically unsaturated polymerizablemonomers from which -A_(i)-recurring units can be derived include:

-   2-cinnamoyl-ethyl methacrylate,-   2-cinnamoyl-ethyl acrylate, and-   2-[3-(3-pyridyl)acryloyl]ethyl methacrylate.

The -A_(i)-recurring units can also be formed after formation of awater-soluble precursor reactive polymer having precursor-A_(i)-recurring units. For example, a water-soluble precursor reactivepolymer can be prepared with recurring units derived from vinyl alcoholsor acrylate monomers having pendant hydroxyl groups, and the pendanthydroxyl groups can be reacted with cinnamoyl chloride (or similarsubstituted cinnamoyl-like chloride reactants) to form the desired-A_(i)-(or similar) recurring units with pendant water-solubilizingsulfonic acid or sulfonate groups already present before the reaction toform the -A_(i)-recurring units.

(ii) Another class of useful photosensitive crosslinkable groupsarranged along the reactive polymer backbone can comprise pendantphotosensitive (crosslinkable), non-aromatic unsaturated carbocyclicgroups including but not limited to, cyclopropene groups, cyclobutenegroups, cyclopentadiene groups, cyclohexene groups, cyclohexadienegroups, cycloheptene groups, cycloheptadiene groups, cycloheptatrienegroups, cyclooctene groups, indene groups, dihydronaphthalene groups,and norbornene groups. Any of these photosensitive groups can besubstituted with one or more substituents that will not interfere withthe desired properties of the reactive polymer. Where appropriate, suchnon-aromatic unsaturated carbocyclic groups can also contain one or morecarbon-containing fused rings. The cyclopropene groups including theunsaturated cyclopropene groups can be particularly useful.

In general, such useful recurring units can be represented by thefollowing Structure (-A_(ii)-):

Specifically, R, R¹, and R² in Structure (-A_(ii)-) can be independentlyhydrogen or substituted or unsubstituted alkyl groups having at least 1to 7 carbon atoms (including substituted or unsubstituted methyl, ethyl,isopropyl, t-butyl, hexyl, and benzyl groups, and others that would bereadily apparent to one skilled in the art), substituted orunsubstituted cycloalkyl group having 5 or 6 carbon atoms in the ring(such as cyclopentyl, cyclohexyl, 4-methylcyclohexyl, and others thatwould be readily apparent to one skilled in the art), substituted orunsubstituted phenyl groups (such as phenyl, tolyl, and xylyl groups,and others that would be readily apparent to one skilled in the art),substituted or unsubstituted alkoxy groups having 1 to 7 carbon atoms(such as methoxy, ethoxy, benzoxy, and others readily apparent to oneskilled in the art), or substituted or unsubstituted phenoxy groups(such as phenoxy, 2,4-dimethylphenoxy, and others that would be readilyapparent to one skilled in the art). In some embodiments, R and R¹ canalso be nitro, cyano, or halogen groups.

More particularly, R, R¹, and R² in Structure (-A_(ii)-) can beindependently hydrogen or substituted or unsubstituted methyl, ethyl orphenyl groups, and more particularly, each of these groups is hydrogenor methyl.

E can be a divalent linking group including but not limited to,substituted or unsubstituted alkylene (including haloalkylenes andcyanoalkylenes), alkyleneoxy, alkoxyalkylene, iminoalkylene,cycloalkylene, aralkylene, cycloalkylene-alkylene, aryloxyalkylenegroups wherein the divalent hydrocarbon groups can comprise 1 to 20carbon atoms (in either linear, branched, or cyclic form), carbonyloxy,oxycarbonyl, amido, keto, carbonate, carbamate, and urea. Particularlyuseful E divalent groups are substituted or unsubstituted alkylenegroups such as substituted or unsubstituted ethylene or propylenes, oroxycarbonyl.

In Structure (-A_(i)-), D₁ can represent the carbon atoms necessary tocomplete a three-membered to seven-membered non-aromatic unsaturatedcarbocyclic group (or ring), or particularly the carbon atoms necessaryto complete a non-aromatic, unsaturated 3-membered to 7-memberedcarbocyclic group (or ring) such as a cyclopropene ring, a cyclobutenering, a cyclopentene ring, a cyclohexene ring, or a cycloheptene ring.D₁ can also represent the saturated or unsaturated carbon atoms toprovide an indene or dihydronaphthalene group, or polycyclic rings suchas a norbornene group.

Moreover, in Structure (-A_(ii)-), R³ can be hydrogen, a substituted orunsubstituted alkyl group having 1 to 12 carbon atoms (such as methyl,ethyl, isopropyl, amyl, hexyl, nonyl, decyl, and dodecyl), or asubstituted or unsubstituted aryl group having 6 or 10 carbon atoms inthe ring. Such groups can be substituted with one or more hydroxy,halogen, carbonyl, cyano, alkyl, or alkoxy groups.

In Structure (-A_(ii)-), m can represent the molar amounts of therecurring units that would satisfy the amounts described above for thewater-soluble polymer.

Some particularly useful (b) recurring units of this type represented bythe following Structure (-A_(ii2)-) or (-A_(ii3)-):

wherein R, R¹, R², R³, and E are as defined above for Structure(-A_(i)-).

Some useful recurring units of this type can be derived from:

-   2-cyclopropene-1-carboxylic acid, 2,3-diphenyl-,    2-[(2-methyl-1-oxo-2-propen-1-yl)oxy]ethyl ester;-   2-cyclopropene-1-carboxylic acid, 2,3-diphenyl-,    2-[(2-methyl-1-oxo-2-propen-1-yl)amino]ethyl ester;-   4-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy) styrene;-   4-(2,3-diphenyl-2-cyclopropene-1-carbonylamino) styrene; and-   4-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy)ethane.

Class (iii) photosensitive crosslinking groups in the reactive polymerscomprise pendant photosensitive (crosslinkable), non-aromaticheterocyclic groups, each of which comprises a carbon-carbon double bond(>C═C<) that is conjugated with one or more electron withdrawing groups.In many embodiments, the carbon-carbon double bond is conjugated withone or two of the same or different electron withdrawing groups, and inmost embodiments, the carbon-carbon double bond is conjugated with onlyone electron withdrawing group.

It is to be understood that the pendant photosensitive, non-aromaticheterocyclic groups can be single ring groups formed of carbon andhetero atoms (such as nitrogen, sulfur, and oxygen), or they can befused ring groups with two or more fused rings formed from carbon andsuitable heteroatoms.

Useful electron withdrawing groups that can be conjugated with thecarbon-carbon double bond would be readily apparent to one skilled inthe art as the term “electron withdrawing” in reference to a chemicalgroup is well known in the art. However, it is particularly useful whensuch electron withdrawing groups include but are not limited to,carbonyl, ester, thioester, amide, imine, amidine, ether, thioether, andamine groups (or moieties). More generally, the photosensitive(crosslinkable) non-aromatic heterocyclic group can be a cyclic groupthat comprises an α,β-unsaturated ketone, α,β-unsaturated lactone,α,β-unsaturated lactam, α,β-unsaturated ether, α,β-unsaturatedthioether, or α,β-unsaturated amine group. Of these types ofphotosensitive (crosslinkable) non-aromatic heterocyclic groups, thosecontaining a carbonyl group are particularly useful.

For example, the reactive polymers can comprise pendant photosensitive,non-aromatic heterocyclic groups selected from the group consisting ofcoumarin, thiocoumarin, quinone, benzoquinone, naphthoquinone, pyran,thiopyran, benzopyran, benzothiopyran, pyranone, thiopyranone,pyridinone, quinoline, and quinolinone groups. Of these photosensitivenon-aromatic heterocyclic groups, pendant photosensitive coumarin orquinolinone groups are useful and the pendant photosensitive coumaringroups are most useful because they can be readily prepared.

Any of the photosensitive non-aromatic heterocyclic groups can besubstituted with one or more substituents that will not interfere withthe desired properties of the reactive polymer.

In general, useful (b) recurring units can be represented by thefollowing Structure (-A_(iii)-):

Specifically, in Structure (-A_(iii)-), R, R¹, and R² can beindependently hydrogen or substituted or unsubstituted alkyl groupshaving at least 1 to 7 carbon atoms (including substituted orunsubstituted methyl, ethyl, isopropyl, t-butyl, hexyl, and benzylgroups, and others that would be readily apparent to one skilled in theart), substituted or unsubstituted cycloalkyl group having 5 or 6 carbonatoms in the ring (such as cyclopentyl, cyclohexyl, 4-methylcyclohexyl,and others that would be readily apparent to one skilled in the art),substituted or unsubstituted phenyl groups (such as phenyl, tolyl, andxylyl groups, and others that would be readily apparent to one skilledin the art), substituted or unsubstituted alkoxy groups having 1 to 7carbon atoms (such as methoxy, ethoxy, benzoxy, and others readilyapparent to one skilled in the art), or substituted or unsubstitutedphenoxy groups (such as phenoxy, 2,4-dimethylphenoxy, and others thatwould be readily apparent to one skilled in the art). In someembodiments, R and R¹ can also be nitro, cyano, or halogen groups.

More particularly, R, R¹, and R² can be independently hydrogen orsubstituted or unsubstituted methyl, ethyl or phenyl groups, and moreparticularly, each of these groups can be hydrogen or methyl.

E in Structure (-A_(iii)-) can be a single bond or divalent linkinggroup that can be connected to a carbon atom within D₁. Thus, while Eappears to be connected directly to D₁, E can be connected to any carbonrepresented by Dr. For example, E can be a divalent linking groupincluding but not limited to, substituted or unsubstituted alkylene(including haloalkylenes and cyanoalkylenes), alkyleneoxy,alkoxyalkylene, iminoalkylene, cycloalkylene, aralkylene,cycloalkylene-alkylene, aryloxyalkylene groups wherein the divalenthydrocarbon groups can comprise 1 to 20 carbon atoms (in either linear,branched, or cyclic form), carbonyloxy, oxycarbonyl, amido, keto,carbonate, carbamate, and urea. A skilled worker in polymer chemistrywould be able to design other useful linking groups using suitablenumber of carbon and hetero (oxygen, nitrogen, or sulfur) atoms in anorder and arrangement that are chemically possible. Particularly usefulE divalent groups are substituted or unsubstituted alkylene groups suchas substituted or unsubstituted ethylene or propylenes or oxycarbonyl.

In Structure (-A_(iii)-), D₁ represents the carbon and hetero (sulfur,oxygen, or nitrogen particularly) atoms necessary to complete athree-membered to fourteen-membered non-aromatic heterocyclic group (orring) that includes the carbon-carbon double bond shown in Structure(-A_(iii)-). However, it is essential that either D₁ or at least one ofthe R³ groups (defined below) comprises at least one (and optionallymore) electron withdrawing groups that are conjugated with thecarbon-carbon double bond shown in Structure (-A_(iii)-).

D₁ can also represent the saturated or unsaturated carbon or heteroatoms to provide one or more fused rings such as naphthoquinone,benzopyran, benzothiopyran, benzopyran-2-one (coumarin), quinoline, andquinolinone polyrings. Other useful D₁ ring systems optionallycomprising at least one electron withdrawing group that is conjugatedwith the carbon-carbon double bond would be readily apparent to oneskilled in the art.

Moreover, in Structure (-A_(iii)-), R³ is hydrogen, a substituted orunsubstituted alkyl group having 1 to 12 carbon atoms (such as methyl,ethyl, isopropyl, amyl, hexyl, nonyl, decyl, and dodecyl), a substitutedor unsubstituted aryl group having 6 or 10 carbon atoms in the ring, asubstituted or unsubstituted alkoxy group having 1 to 12 carbon atoms(such as methoxy, 2-ethoxy, t-butoxy, and n-hexoxy), substituted orunsubstituted aryloxy group having 6 or 10 carbon atoms in the ring(such as phenoxy and naphthoxy), cyano, halo, or carbonyl-containinggroup. Such carbonyl-containing groups include but are not limited to,aldehyde, ketone, carboxylic acid, ester, and amide groups. Suchcarbonyl-containing groups can be conjugated with the carbon-carbondouble bond in Structure (A).

In Structure (-A_(iii)-), m can represent the molar amounts of the notedrecurring units as described above for the reactive polymers.

Some useful recurring units of this type can be derived from:

-   7-(2-methacryloyloxyethoxy)-4-methylcoumarin,-   7-(2-methacryloyloxyethoxy)-coumarin,-   7-(3-methacryloyloxysulfopropyl)-4-methylcoumarin,-   7-(methacryloyloxy)-4-methylcoumarin,-   6-(methacryloyloxy)-4-methylcoumarin,-   6-(2-methacryloyloxyethoxy)-4-methylcoumarin,-   7-(2-methacryloyloxyethoxy)-quinoline-2-one,-   7-(2-methacryloyloxyethoxy)-4-methylquinoline-2-one, and-   5-(2-methacryloyloxyethoxy)-naphthoquinone.

Yet another class (iv) comprise pendant photosensitive (crosslinkable),non-aromatic unsaturated heterocyclic groups, each of which non-aromaticunsaturated heterocyclic groups can comprise one or more amide groups[>N—C(═O)—], and each of the amide groups is arranged in theheterocyclic group (ring) in conjugation with a carbon-carbon doublebond (>C═C<). In many embodiments, such heterocyclic groups have onlyone or two amide groups and the carbon-carbon double bond is conjugatedwith the one or two amide groups arranged within the non-aromaticunsaturated heterocyclic group (ring). In most embodiments, thecarbon-carbon double bond is conjugated with the only one amide group inthe non-aromatic unsaturated heterocyclic group (ring).

It is to be understood that the pendant photosensitive, non-aromaticunsaturated heterocyclic groups can be single ring groups formed ofcarbon and hetero atoms (such as nitrogen, sulfur, and oxygen), or theycan be fused ring groups with two or more fused rings formed from carbonand suitable heteroatoms. In most embodiments, the photosensitive,non-aromatic unsaturated heterocyclic groups are single ring groupshaving 5 to 7 carbon and heteroatoms (usually nitrogen atoms) formingthe ring. At least one, and likely two of the carbon atoms in the ringsalso form carbonyl (>C═O) groups.

Particularly useful reactive polymers can comprise pendantphotosensitive, non-aromatic unsaturated heterocyclic groups selectedfrom the group consisting of substituted or unsubstituted maleimide andthymine groups. Of these photosensitive non-aromatic unsaturatedheterocyclic groups, the substituted maleimide groups are most usefulbecause they can be readily prepared.

Any of the photosensitive non-aromatic unsaturated heterocyclic groupscan be substituted with one or more substituents that will not interferewith the desired properties of the reactive polymer and the reactionsnecessary for crosslinking.

In general, useful (b) recurring units can be represented by thefollowing Structure (-A_(iv)-):

In Structure (-A_(iv)-), R, R′, and R″ can be independently hydrogen orsubstituted or unsubstituted alkyl groups having at least 1 to 7 carbonatoms (including substituted or unsubstituted methyl, ethyl, isopropyl,t-butyl, hexyl, and benzyl groups, and others that would be readilyapparent to one skilled in the art), substituted or unsubstitutedcycloalkyl group having 5 or 6 carbon atoms in the ring (such ascyclopentyl, cyclohexyl, 4-methylcyclohexyl, and others that would bereadily apparent to one skilled in the art), substituted orunsubstituted phenyl groups (such as phenyl, tolyl, and xylyl groups,and others that would be readily apparent to one skilled in the art),substituted or unsubstituted alkoxy groups having 1 to 7 carbon atoms(such as methoxy, ethoxy, benzoxy, and others readily apparent to oneskilled in the art), or substituted or unsubstituted phenoxy groups(such as phenoxy, 2,4-dimethylphenoxy, and others that would be readilyapparent to one skilled in the art). In some embodiments, R, R′, and R″can also be nitro, cyano, or halogen groups.

More particularly, R, R′, and R″ can be independently hydrogen orsubstituted or unsubstituted methyl, ethyl or phenyl groups, and moreparticularly, each of these groups can be hydrogen or methyl.

In Structure (-A_(iv)-), L can be a single bond or divalent linkinggroup that can be connected to a nitrogen atom (as shown) within thephotosensitive non-aromatic unsaturated heterocyclic group. For example,L can be a divalent hydrocarbon or aliphatic linking group thatgenerally include 1 to 10 carbon, nitrogen, or oxygen atoms in the chainand can include but not limited to, substituted or unsubstitutedalkylene (including haloalkylenes and cyanoalkylenes); alkyleneoxy;alkoxyalkylene; iminoalkylene; cycloalkylene; aralkylene;cycloalkylene-alkylene; or aryloxyalkylene groups wherein the divalenthydrocarbon groups can comprise 1 to 20 carbon atoms (in either linear,branched, or cyclic form) and can be connected or interrupted withheteroatom-containing groups such as oxy, carbonyl, carbonyloxy,oxycarbonyl, amino, amido, carbonate, carbamate, and urea, or anycombination thereof. A skilled worker in polymer chemistry would be ableto design other useful linking groups using suitable number of carbonand hetero (oxygen, nitrogen, or sulfur) atoms in an order andarrangement that are chemically possible. Particularly useful L divalentgroups are substituted or unsubstituted alkylene groups such assubstituted or unsubstituted methylene, ethylene, or a propylene (anyisomer), or such groups can be used in combination with an oxycarbonyl(such as from an acrylic acid ester group).

In Structure (-A_(iv)-), X represents the 1 to 3 carbon and heteroatoms(usually nitrogen atoms), which in combination with the remaining shownnitrogen and carbon atoms, complete a five- to seven-memberedphotosensitive non-aromatic unsaturated heterocyclic ring. In mostembodiments, X represents at least one carbon atom (for example, acarbonyl carbon atom), or at least one carbon atom (for example, acarbonyl carbon atom) and at least one nitrogen atom such that theresulting amide group is conjugated with the shown carbon-carbon doublebond.

In Structure (-A_(iv)-), R¹ and R² are independently hydrogen or asubstituted or unsubstituted alkyl group having 1 to 10 carbon atoms(such as substituted or unsubstituted methyl, ethyl, isopropyl, amyl,hexyl, nonyl, and decyl groups), or a substituted or unsubstitutedcycloalkyl group having 5 or 6 carbon atoms in the unsaturatedcarbocyclic ring (such as substituted cyclohexyl groups). R¹ and R² arelikely to be the same group such as hydrogen, or unsubstituted methyl orunsubstituted ethyl groups.

Some particular useful representations of such (b) recurring units areshown in the following Structures (-A_(iv1)-), (-A_(iv2)-), and(-A_(iv3)-)

wherein R, R′, R″, L, R¹, and R² are as defined above in Structure(-A_(iv)-) and m is defined below.

Moreover, in Structures (-A_(iv2)-) and (-A_(iv3)-), R³ and R⁴ areindependently hydrogen, or substituted or unsubstituted alkyl groups orsubstituted or substituted cycloalkyl groups for example as used todefine R¹ and R² shown above.

It should be understood that a reactive polymer used in this inventioncan comprise a variety of different photosensitive non-aromaticunsaturated heterocyclic groups in recurring units. For example, thereactive polymer can have recurring units represented by both Structures(-A_(iv1)-) and either (-A_(iv2)-) or (-A_(iv3)-). Alternatively, thereactive polymer can have recurring units represented by both Structures(-A_(iv2)-) and (-A_(iv3)-). Still again, the reactive polymer can haverecurring units represented by all of Structure (-A_(iv1)-),(-A_(iv2)-), and (-A_(iv3)-).

Still another class (v) of useful photosensitive and crosslinkablependant groups comprises photosensitive substituted or unsubstituted1,2-diarylethylene groups. Such groups can be generally represented as—Ar₁-ethylene-Ar₂ wherein Ar₁ is a divalent, substituted orunsubstituted heterocyclic or carbocyclic aromatic group and Ar₂ is amonovalent, substituted or unsubstituted heterocyclic or carbocyclicaromatic group.

For example, some useful reactive polymers comprise pendant groupscomprising photosensitive substituted or unsubstituted 1,2-diarylethylene groups selected from stilbene, styrylnaphthalene,styrylpyridine, styrylpyridinium, styrylquinoline, styrylquinolinium,styrylthiazole, styrylthiazolium, naphthrylphenyl(naphthylene-ethylene-phenyl), naphthrylpyridinium, naphthylthiazolium,1-pyridyl-2-thiazolylethylene, and 1,2-pyridiylethylene groups. Thependant groups comprising photosensitive stilbene, styrylpyridinium,styrylquinoline, or styrylthiazolium groups are particularly useful.

Any of the photosensitive 1,2-diarylethylene groups can be substitutedwith one or more substituents that will not interfere with the desiredproperties of the reactive polymer and the reactions necessary forcrosslinking.

In general, such useful (b) recurring units can be represented by thefollowing Structure (-A_(v)-) showing both reactive polymer backbone andpendant groups attached thereto:

In Structure (-A_(v)-), R, R′, and R″ can be independently hydrogen orsubstituted or unsubstituted alkyl groups having at least 1 to 7 carbonatoms (including substituted or unsubstituted methyl, ethyl, isopropyl,t-butyl, hexyl, and benzyl groups, and others that would be readilyapparent to one skilled in the art), substituted or unsubstitutedcycloalkyl group having 5 or 6 carbon atoms in the ring (such ascyclopentyl, cyclohexyl, 4-methylcyclohexyl, and others that would bereadily apparent to one skilled in the art), substituted orunsubstituted phenyl groups (such as phenyl, tolyl, and xylyl groups,and others that would be readily apparent to one skilled in the art),substituted or unsubstituted alkoxy groups having 1 to 7 carbon atoms(such as methoxy, ethoxy, benzoxy, and others readily apparent to oneskilled in the art), or substituted or unsubstituted phenoxy groups(such as phenoxy, 2,4-dimethylphenoxy, and others that would be readilyapparent to one skilled in the art). In some embodiments, R, R′, and R″can also be nitro, cyano, or halogen groups.

More particularly, R, R′, and R″ can be independently hydrogen orsubstituted or unsubstituted methyl, ethyl or phenyl groups, and moreparticularly, each of these groups can be hydrogen or substituted orunsubstituted methyl groups.

In Structure (-A_(v)-), L can be a single bond or divalent linking groupthat can be connected to a nitrogen atom (as shown) within thephotosensitive non-aromatic unsaturated heterocyclic group. For example,L can be a divalent hydrocarbon or aliphatic linking group thatgenerally include 1 to 10 carbon, nitrogen, or oxygen atoms in the chainand can include but not limited to, substituted or unsubstitutedalkylene (including haloalkylenes and cyanoalkylenes); alkyleneoxy;alkoxyalkylene; iminoalkylene; cycloalkylene; aralkylene;cycloalkylene-alkylene; or aryloxyalkylene groups wherein the divalenthydrocarbon groups can comprise 1 to 20 carbon atoms (in either linear,branched, or cyclic form) and can be connected or interrupted withheteroatom-containing groups such as oxy, carbonyl, carbonyloxy,oxycarbonyl, amino, amido, carbonate, carbamate, and urea, or anycombination thereof. A skilled worker in polymer chemistry would be ableto design other useful linking groups using suitable number of carbonand hetero (oxygen, nitrogen, or sulfur) atoms in an order andarrangement that are chemically possible. Particularly useful L divalentgroups can be substituted or unsubstituted alkylene groups such assubstituted or unsubstituted methylene, ethylene, or a propylene (anyisomer), or such groups can be used in combination with an oxycarbonyl(such as from an acrylic acid ester group), and aliphatic groupscomprising a carbonyloxy group directly attached to the reactive polymerbackbone.

Moreover, in Structure (-A_(v)-), Ar₁ is a divalent carbocyclic orheterocyclic aromatic group that can be substituted or unsubstituted.For example, Ar₁ can be substituted or unsubstituted phenylene,substituted or unsubstituted naphthylene, substituted or unsubstitutedpyridinylene, substituted or unsubstituted quinolinylene, substituted orunsubstituted thiazolylene, substituted or unsubstituted pyridinium,substituted or unsubstituted quinolinium, or substituted orunsubstituted thiazolium. As would be understood by one skilled in theart, some of the useful Art groups can be quaternary aromatic ringswherein a nitrogen atom in the aromatic ring is optionally attached to Lor is quaternized in a suitable manner, and suitable counterions can bepresent such as a trifluoromethylsulfonate counterion. When the Ar₁rings are substituted, the one or more substituents can be any moietythat will not adversely affect the photosensitivity of the pendant groupor any other properties intended for the reactive polymer. For example,useful substituents can include but are not limited to methyl groups andethyl groups. Particularly useful Ar₁ groups are substituted orunsubstituted phenylene and pyridinium groups.

Ar₂ can be a substituted or unsubstituted carbocyclic or heterocyclicaromatic group as defined for Art except that Ar₂ is monovalent as shownin Structure (-A_(v)-). Particularly useful Ar₂ groups are substitutedor unsubstituted phenyl, substituted or unsubstituted naphthalene,substituted or unsubstituted pyridine, substituted or unsubstitutedpyridinium, substituted or unsubstituted quinoline, substituted orunsubstituted quinolinium, substituted or unsubstituted thiazole, andsubstituted or unsubstituted thiazolium groups, with substituted orunsubstituted phenyl, substituted or unsubstituted pyridinium,substituted or unsubstituted quinolinium groups, and substituted orunsubstituted thiazolium groups being particularly useful. Similarly toArt, some of the Ar₂ aromatic rings can be quaternary aromatic ringshaving a positive nitrogen atom, and a suitable counterion, such as ahalide or trifluoromethylsulfonate, is then present. A skilled worker inthe art would readily know about other suitable counterions.

Moreover, In Structure (-A_(v)-), R¹ and R² are independently hydrogenor substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms(such as substituted or unsubstituted methyl, ethyl, isopropyl, amyl,hexyl, nonyl, and decyl groups), or substituted or unsubstitutedcycloalkyl groups having 5 or 6 carbon atoms in the unsaturatedcarbocyclic ring (such as substituted cyclohexyl groups). R¹ and R² arelikely to be the same group such as hydrogen, or unsubstituted methyl orunsubstituted ethyl groups.

In some embodiments, the reactive polymer comprises (b) recurring unitsrepresented by the following Structure (-A_(v1)-) also showing reactivepolymer backbone to which pendant groups are attached:

wherein R, R′, R″ are as defined above and are particularly hydrogen ormethyl, L is as described above and particularly comprises a carbonyloxygroup directly attached to the backbone, R¹ and R² can be independentlyhydrogen, methyl, or ethyl, R³ can be a suitable substituted orunsubstituted alkyl, substituted or unsubstituted cycloalkyl, orsubstituted or unsubstituted aryl group, X⁻ can be a suitable counterionas described above, and m is as defined below.

In Structures (-A_(v)-) and (-A_(v1)-), m can represent the molaramounts of the (b) recurring units as described above for the reactivepolymers.

Some useful (b) recurring units of this class can be derived from:

-   1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]pyridinium    trifluormethylsulfonate;-   1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]quinolinium    trifluoromethylsulfonate;-   1-methyl-2-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]thiazolium    trifluoromethylsulfonate;-   4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]pyridine;    and-   1-phenyl-2-[(4-(2-methacryloxyethyl)-carbonyloxyphenyl)]ethylene.

Such useful (b) recurring units can be derived from suitableethylenically unsaturated polymerizable monomers that can then bepolymerized under suitable conditions to provide useful reactivepolymers. More likely, such monomers are prepared by attaching a1,2-diarylethylene group to a polymerizable acrylic group through alinking group by formation of an ester, amide or ether bond. For example4-formylbenzoic acid can be easily condensed with 4-methylpyridine toform a styrylpyridine group with a carboxylic acid functionalitysuitable for attachment to a linking group on an acrylic monomer such as2-hydroxyethylmethacrylate. The carboxylic acid and the hydroxyethylgroups can then be attached by a variety of ester forming reactions wellknown in the art including the known Mitsunobu reaction.

Optional (c) and (d) Recurring Units:

The reactive polymers used in the present invention can optionallycomprise at least 1 mol % and up to and including 93 mol %, or typicallyat least mol % and up to and including 70 mol %, of (c) recurring unitscomprising pendant amide, hydroxyl, lactam, phosphonic acid (orphosphonate), or carboxylic acid (or carboxylate) groups, all based onthe total amount of recurring units in the reactive polymer,particularly when (a2) recurring units are present.

Recurring units comprising pendant hydroxyl, amide, or carboxylic acidgroups are particularly useful. It is also useful to have (c) recurringunits that comprise multiple different pendant groups from the notedlist of pendant groups. If the (a1) recurring units are present in thereactive polymer, any (c) recurring units that are present would bedifferent from those chosen for the (a1) recurring units, for examplethe (c) recurring units can comprise pendant amide, hydroxyl, or lactamgroups or pendant precursor moieties for the pendant amide, hydroxyl, orlactam groups.

When the (a2) recurring units are present, useful pendant precursorgroups for the (c) recurring units include but are not limited to,anhydrides, alcohols, amines, lactam, lactone, amide, and ester groupsthat can be used to provide the various groups noted above for the (c)recurring units.

For example, useful (c) recurring units can be represented by thefollowing Structure (—C—):

wherein B′ represents a pendant amide, hydroxy, lactam, phosphonic acid,or carboxylic acid group or precursor groups that can be appropriatelyconverted, which group can be directly attached to the reactive polymerbackbone or it can be attached through a suitable divalent linkinggroup.

For example, some useful ethylenically unsaturated polymerizablemonomers from which the (c) recurring units can be derived include butare not limited to, (meth)acrylic acid, itaconic acid, maleic anhydride,fumaric acid, maleic acid, citraconic acid, vinyl benzoic acid,2-carboxyethyl acrylate, 2-carboxyethyl methacrylate, (meth)acrylamide,N-vinyl pyrrolidone, 2-hydroxyethyl methacrylate, 2-aminoethylmethacrylate, vinyl phosphonic acid, N-isopropyl acrylamide, anddimethyl acrylamide.

In addition to the (a1), (a2), (b), and (c) recurring units describedabove, the reactive polymers can optionally comprise one or moreadditional recurring units that are different from all (a1), (a2), (b),and (c) recurring units, and herein identified as optional (d) recurringunits, in an amount of less than 50 mol %, based on the total recurringunits in the reactive polymer. Alternatively, (d) recurring units can bepresent with (a1), (a2), and (b) recurring units but (c) recurring unitsare absent.

A skilled polymer chemist would understand how to choose such additional(d) recurring units, and for example, they can be derived from one ormore ethylenically unsaturated polymerizable monomers selected from thegroup consisting of alkyl acrylates, alkyl methacrylates, styrene andstyrene derivatives, vinyl ethers, vinyl benzoates, vinylidene halides,vinyl halides, vinyl imides, and other materials that a skilled workerin the art would understand could provide desirable properties to thereactive polymer. Such (d) recurring units can be represented byStructure (-D-) as follows:

wherein the pendant D groups in Structure (-D-) can be for example,hydrogen, substituted or unsubstituted alkyl groups, substituted orunsubstituted aryl groups, alkyl ester groups, aryl ester groups,halogens, or ether groups.

In addition, some (d) recurring units can comprise an epoxy (such as aglycidyl group) or epithiopropyl group derived for example from glycidylmethacrylate or glycidyl acrylate.

In the recurring units described above, R, R′, and R″ can be the same ordifferent hydrogen, methyl, ethyl, or chloro groups and each type ofrecurring unit can have the same or different R, R′, and R″ groups alongthe reactive polymer backbone. In most embodiments, R, R′, and R″ arehydrogen or methyl, and R, R′, and R″ can be the same or different forthe various (a1), (a2), (b), (c), and (d) recurring units in a givenreactive polymer.

In the Structures shown above, “m,” “n,” and “p” are used to representthe respective molar amounts of recurring units, based on the totalrecurring units in a given reactive polymer, so that the sum of m, n,and p equal 100 mol % in a given reactive polymer.

The mol % amounts of the various recurring units defined herein for thereactive polymers defined herein are meant to refer to the actual molaramounts present in the reactive polymers. It is understood by oneskilled in the art that the actual mol % values may differ from thosetheoretically possible from the amount of ethylenically unsaturatedpolymerizable monomers that are used in the polymerization reactionsolution. However, under most polymerization conditions that allow highpolymer yield and optimal reaction of all monomers, the actual mol % ofeach monomer is generally within +15 mol % of the theoretical amounts.

Representative reactive polymer embodiments include but are not limitedto, the following copolymers wherein the molar ratios are theoretical(nominal) amounts based on the actual molar ratio of ethylenicallyunsaturated polymerizable monomers used in the polymerization process.The actual molar amounts of recurring units can differ from thetheoretical (nominal) amounts of monomers if the polymerizationreactions are not carried out to completion.

-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-cinnamoyl-ethyl    methacrylate) (80:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-cinnamoyl-ethyl    methacrylate) (70:30 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-cinnamoyl-ethyl    methacrylate) (50:50 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (30:50:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (10:70:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (5:75:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (5:85:10 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (5:90:5 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (2:78:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methyl    metharylate-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-butyl    metharylate-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-styrene-co-2-cinnamoyl-ethyl    methacrylate) (70:10:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic acid-co-butyl    methacrylate-co-2-cinnamoyl-ethyl methacrylate) (10:60:10:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-styrene-co-2-cinnamoyl-ethyl methacrylate) (10:65:5:20 mol    %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-acrylamide-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol    %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-acrylamide-co-2-cinnamoyl-ethyl methacrylate) (10:70:20 mol    %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-hydroxyethyl    metacrylate-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-hydroxyethyl    metacrylate-co-2-cinnamoyl-ethyl methacrylate) (10:70:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-maleic    anhydryde-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-maleic    anhydryde-co-2-cinnamoyl-ethyl methacrylate) (10:70:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-N-vinyl-2-pyrrolidone-co-2-cinnamoyl-ethyl methacrylate)    (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-vinyl phosphonic    acid-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic    acid-co-2-cinnamoyl-ethyl methacrylate) (80:20 mol %);-   Poly(2-acylamide-2-methyl-I-propanesulfonic acid-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-methacrylic    acid-co-2-cinnamoyl-ethyl methacrylate) (10:70:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic    acid-co-acrylamide-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol    %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-2-hydroxyethyl    methacrylate-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-maleic    anhydryde-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic    acid-co-N-vinyl-2-pyrrolidone-co-2-cinnamoyl-ethyl methacrylate)    (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-vinyl phosphonic    acid-co-2-cinnamoyl-ethyl methacrylate) (50:30:20 mol %);-   Poly(styrene sulfonic acid sodium salt-co-2-cinnamoylethyl    methacrylate) (80:20 mol %);-   Poly(styrene sulfonic acid sodium salt-co-methacrylic    acid-co-2-cinnamoylethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl acrylate sodium salt-co-methacrylic    acid-co-2-cinnamoylethyl methacrylate) (50:30:20 mol %);-   Poly(2-sulfoethyl methacrylate sodium salt-co-methacrylic    acid-co-2-cinnamoylethyl methacrylate) (50:30:20 mol %);-   Poly(4-sulfobutyl methacrylate sodium salt-co-methacrylic    acid-co-2-cinnamoylethyl methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (80:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (30:50:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (10:70:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-acrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-acrylamide-co-7-(2-methacryloxyethoxy)-4-methylcoumarin)    (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-2-hydroxyethyl    methacrylate-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20    mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-maleic    anhydryde-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20    mol %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-N-vinyl-2-pyrrolidone-co-7-(2-methacryloxyethoxy)-4-methylcoumarin)    (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium salt-co-vinyl phosphonic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate potassium    salt-co-N-vinyl-2-pyrrolidone-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (20:30:30:20 mol    %);-   Poly(styrene sulfonic acid sodium    salt-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (80:20 mol %);-   Poly(styrene sulfonic acid sodium salt-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (80:20 mol %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-methacrylic    acid-co-7-(2-methacryloxyethoxy)-4-methylcoumarin) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-N-(2-(methacryloxy)ethyl)    dimethylmaleimide-) (80:20 mol %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-N-(2-(methacryloxy)ethyl) dimethylmaleimide-) (50:30:20 mol    %);-   Poly(3-sulfopropyl methacrylate-co-methacrylic    acid-co-N-(2-(methacryloxy)ethyl) dimethylmaleimide-) (10:70:20 mol    %);-   Poly(styrene sulfonic acid sodium salt-co-methacrylic    acid-co-N-(2-(methacryloxy)ethyl) dimethylmaleimide-) (50:30:20 mol    %);-   Poly(2-acylamide-2-methyl-1-propanesulfonic acid-co-methacrylic    acid-co-N-(2-(methacryloxy)ethyl) dimethylmaleimide-) (50:30:20 mol    %);-   Poly[3-sulfopropyl methacrylate-co-3N-(2-(methacryloxy)ethyl    thymine] (80:20 mol %);-   Poly[3-sulfopropyl methacrylate-co-methacrylic    acid-co-3N-(2-(methacryloxy)ethyl-thymine] (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate sodium salt-co-methacrylic    acid-co-2-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy) ethyl    methacrylate) (50:30:20 mol %);-   Poly(3-sulfopropyl methacrylate sodium salt-co-methacrylic    acid-co-2-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy) ethyl    methacrylate) (10:70:20 mol %);-   Poly(2-acrylamindo-2-methyl-1-propanesulfonic acid-co-methacrylic    acid-co-2-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy) ethyl    methacrylate) (10:70:20 mol %);-   Poly(styrene sulfonic acid sodium salt-co-methacrylic    acid-co-2-(2,3-diphenyl-2-cyclopropene-1-carbonyloxy) ethyl    methacrylate) (10:70:20 mol %/0);-   Poly[3-sulfopropyl    methacrylate-co-1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]pyridinium    trifluoromethylsulfonate] (80:20 mol %);-   Poly[3-sulfopropyl methacrylate-co-methacrylic    acid-co-1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]pyridinium    trifluoromethylsulfonate] (10:70:20 mol %);-   Poly[3-sulfopropyl methacrylate-co-methacrylic    acid-co-1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]quinolinium    trifluoromethylsulfonate] (30:50:20 mol %);-   Poly[3-sulfopropyl methacrylate-co-methacrylic    acid-co-1-methyl-2-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]thiazolium    trifluoromethylsulfonate-co-methacrylic acid] (20:60:20 mol %);-   Poly[styrene sulfonic acid-co-methacrylic    acid-co-1-methyl-4-[2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]pyridine]    (50:30:20 mol %); and-   Poly[styrene sulfonic acid sodium    salt-co-2-(4-(2-methacryloxyethyl)-carbonyloxyphenyl)ethenyl]phenyl]    (80:20 mol %).

The reactive polymers useful in the invention generally have a molecularweight (M_(w)) of at least 10,000 and up to and including 1,000,000, orat least 20,000 and up to and including 500,000, or even at least 30,000and up to and including 200,000, all as measured by gel permeationchromatography (GPC) or by size exclusion chromatography (SEC).

Preparation of the reactive polymers useful in the present invention canbe accomplished by free radical initiated polymerization in theappropriate reaction solvent combination. The proper choice of reactionsolvents is desirable for successful polymerization because of the widedisparity in polarity between the various ethylenically unsaturatedpolymerizable monomers with the ethylenically unsaturated polymerizablemonomers providing the (a) recurring units being very polar ornegatively charged and water soluble and the ethylenically unsaturatedpolymerizable monomers that provide (b) recurring units being relativelynon-polar and hydrophobic. It is typical to require up to three reactionsolvents in combination to facilitate a well-controlled polymerization.Useful reaction solvents include but are not limited to, water, ketonessuch as methyl ethyl ketone, aprotic polar solvents such asN,N-dimethylacetamide, and alcohols such as isopropyl alcohol. Readilyavailable free radical initiators such as2,2′-azodi(2-methylbutyronitrile) (AMBN) or azobis(isobutyronitrile)(AIBN) generally work well in these preparations of the reactionpolymers. The polymerization reaction is typically carried out at 60° C.to 75° C. for about 18 hours. Controlled or living radicalpolymerization methods (see for example, Qui et al., Progress in PolymerScience 26 (2001) 2083-2134) that can produce very narrow molecularweight distributions and highly controlled block copolymers could alsobe used.

Purification of useful reactive polymers is best accomplished bydialysis because of their high water solubility. Additional water can beadded to the completed reaction mixture that is then placed in adialysis bag with a typical retention of polymer chains with an M_(w) of3500 Daltons or more. The dialysis bag containing the crude reactivepolymer is placed in a water washing bath for 1 to 2 days or longer ifneeded. After dialysis, the dilute reactive polymer solution can beconcentrated by evaporation to from 10 weight % to 20 weight % solidswhich is suitable for storage and dilution to desired coatingconcentrations.

One or more reactive polymers described herein can be present in the inkjettable and UV-curable compositions described herein in an amount of atleast 0.1 weight % and up to and including 20 weight %, or at least 1weight % and up to and including 10 weight %, based on the total weightof the ink jettable and UV-curable composition (including the aqueousmedium such as water).

One or more of such reactive polymers can then be dispersed in anacceptable aqueous medium that comprises mostly (at least 70 weight % oftotal aqueous medium) water, or entirely (100%) water, to form inkjettable and UV-curable compositions of the present invention.

In many embodiments, the reactive polymers described herein can becombined with one or more humectants to form ink jettable and UV-curablecompositions of the present invention.

Such humectants are generally water-soluble or water-miscible organicsolvents (sometimes known as co-solvents) having a viscosity that isgreater than 40 centipoise or even at least 1000 centipoise whenmeasured at 25° C. For example, any water-soluble humectant known in theink jet art that is compatible with the reactive polymer can be used. By“water-soluble” is meant that a mixture of the humectant(s) and water ishomogeneous and visually clear.

While an individual humectant can be employed, mixtures of two or morehumectants, each of which imparts a useful property also can be used.

Representative examples of useful humectants include but are not limitedto the following compounds:

(1) polyhydric alcohols (polyols), such as ethylene glycol, diethyleneglycol, triethylene glycol, tetraethylene glycol, propylene glycol,dipropyleneglycol, the polyethylene glycols with average molecularweights of at least 200 to and including 5000 Daltons, the polypropyleneglycols with average molecular weights of at least 200 to and including5000 Daltons, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol,1,3-butanediol, 1,4-butanediol, 1,2,4-butanetriol,3-methyl-1,3-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol,1,6-hexanediol, 2-methyl-2,4-pentanediol, 1,7-heptanediol,2-ethyl-1,3-hexane diol, 2,2,4-trimethyl-1,3-pentane diol, 1,8-octanediol, glycerol, 1,2,6-hexanetriol, 2-ethyl-2-hydroxymethyl-propanediol,2-methyl-2-hydroxymethyl-propanediol, saccharides and sugar alcohols andthioglycol;

(2) polyoxygenated polyols and their derivatives such as diglycerol,polyglycerols, glycerol ethoxides, glycerol propoxides, glyceryths,alkylated and acetylated glyceryths, pentaerythritol, pentaerythritolethoxides, and pentaerythritol propoxides and their alkylated andacetylated derivatives;

(3) sulfur-containing compounds such as 2,2′-thiodiethanol and othersulfonated diols;

(4) cyclic lactams such as pyrrolidinones including as 2-pyrrolidinone,N-hydroxyethyl-2-pyrrolidinone, and N-methyl 2-pyrrolidinone; and

(5) cyclic ureas such as imidazolidones including 2-imidazolidone and1,3-dimethyl-2-imidazolidone.

Of these compounds, ethylene glycol and 2-pyrrolidone are particularlyuseful. Glycerol and polyhydric alcohol derivatives thereof are alsouseful and can be combined with lower viscosity humectants such asethylene glycol or 2-pyrrolidone. The useful humectants have meltingpoints below the typical operating temperature of the intended printersystem to avoid the formation of crystalline deposits on the print heador in the maintenance system.

Practically, this means that the useful humectants have melting pointsbelow 30° C. or even below 20° C.

The one or more humectants can be present in an amount of at least 0.1weight %, or of at least 1 weight % and up to and including 30 weight %,or of at least 1 weight % and up to and including 20 weight %, all basedon the total weight of the ink jettable and UV-curable composition(including water).

Besides the essential reactive polymer described above and anyhumectants described above, the ink jettable and UV-curable compositionscan further comprise one or more of the following optional componentsthat may provide manufacturability, ink jetting, or image properties.

For example, one or more dye or pigment colorants can be present. Ingeneral, such colorants are water-soluble or at least water-dispersibleso that they do not adversely affect ink jetting of the ink jettable andUV-curable compositions. Such dye or pigment colorants can provide anydesired color or hue, and they can be used as mixtures to adjust hues orcolors from the hues or colors that would be provided by each individualdye or pigment colorant.

Useful pigment colorants include but are not limited to, azo pigments,monoazo pigments, disazo pigments, azo pigment lakes, -naphtholpigments, naphthol AS pigments, benzimidazolone pigments, disazocondensation pigments, metal complex pigments, isoindolinone andisoindoline pigments, quinacridone pigments, polycyclic pigments,phthalocyanine pigments, perylene and perinone pigments, thioindigopigments, anthrapyrimidone pigments, flavanthrone pigments, anthanthronepigments, dioxazine pigments, triarylcarbonium pigments, quinophthalonepigments, diketopyrrolo pyrrole pigments, titanium dioxide, iron oxide,and carbon blacks. Specific useful pigment colorants are described inCol. 10 (lines 66) to Col. 11 (line 40) of U.S. Pat. No. 8,455,570(Lindstrom et al.), the disclosure of which is incorporated herein byreference.

Useful organic compounds that are water-soluble or water-dispersible dyecolorants include but are not limited to, Food Black 1, Food Black 2,Food Black 40, Carta Black, Direct Black dyes (4, 14, 17, 22, 27, 38,51, 112, 117, 154, and 168), carboxylated Food Black 286, Acid Blackdyes (1, 7, 9, 24, 26, 48, 52, 58, 60, 61, 63, 92, 107, 109, 118, 119,131, 140, 155, 156, 172, and 194), Acid Red dyes (1, 8, 32, 35, 37, 52,57, 92, 115, 119, 154, 249, 254, and 256), Food Red 40, Direct Red dyes(1, 2, 16, 23, 24, 28, 39, 62, 72, 227, and 236), Direct Red 227, FoodYellow 7, Acid Yellow dyes (3, 7, 17, 19, 23, 25, 29, 38, 42, 49, 59,61, 72. 73, 114, 128, and 151), Direct Yellow dyes (4, 11, 12, 27, 28,33, 34, 39, 50, 58, 86, 100, 106, 107, 118, 127, 132, 142, and 157),Food Blue 1, Acid Blue dyes (1, 7, 9, 25, 40, 45, 62, 78, 80, 92, 102,104, 113, 117, 127, 158, 175, 183, 185, 193, and 209), Direct Blue dyes(1, 6, 8, 14, 15, 25, 71, 76, 78, 80, 86, 90, 106, 108, 123, 163, 165,199, and 226), Direct Blue 199, FD&C Blue 1, Acid Orange 7, and othersthat are known in the art and available from various commercial sources,including those listed in Col. 9 (line 8) to Col. 10 (line 5) of U.S.Pat. No. 6,124,376 (Nichols et al.) which disclosure is incorporatedherein by reference and in Col. 2 (line 65) to Col. 3 (line 23) whichdisclosure is also incorporated herein by reference. Any anionic dyescan be supplied with suitable counterion(s) such as sodium, lithium,quaternary ammonium, or triethanol amine counterions.

A wide variety of water-dispersible organic and inorganic pigments canbe used individually or in combination. For example, a carbon blackpigment can be used alone or combined with a colored pigment such as acyan copper phthalocyanine or a magenta quinacridine pigment. Usefulpigments are described for example in U.S. Pat. No. 5,026,427 (Mitchellet al.), U.S. Pat. No. 5,141,556 (Matrick), U.S. Pat. No. 5,160,370(Suga et al.), and U.S. Pat. No. 5,169,436 (Matrick), the disclosures ofall of which are incorporated herein by reference.

The useful pigment colorants can be accompanied by suitable polymeric ornon-polymeric dispersants that are well known in the art, or the pigmentcolorants can be self-dispersing and thus separate dispersible andstable in the ink jettable and UV-curable compositions without the useof dispersants because of the presence of appropriate surface groups.Examples of useful self-dispersing pigment colorants are described inCol. 11 (lines 49-53) of U.S. Pat. No. 8,455,570 (noted above).

Useful pigment colorants can have a median particle diameter of lessthan 150 nm and more likely less than 100 nm or even less than 50 nm. Asuseful herein, the term “median particle diameter” refers to the 50^(th)percentile of the classified particle size distribution such that 50% ofthe volume of the particles is provided by particles having diameterssmaller than the indicated diameter.

Dye or pigment colorants can be present in each ink jettable andUV-curable composition in an amount of at least 0.1 weight % and up toand including 30 weight %, or more likely of at least 0.2 weight % andup to and including 10 weight %, or even of at least 0.5 weight % and upto and including 8 weight %, based on the total weight of the inkjettable and UV-curable composition (including water).

Other optional additives that can be present in the ink jettable andUV-curable compositions, in amounts that would be readily apparent toone skilled in the art, include but are not limited to, thickeners;conductivity-enhancing agents; drying agents; waterfast agents;viscosity modifiers; pH buffers; antifoamants; wetting agents; corrosioninhibitors; biocides (such as Kordek and Proxel); fungicides; defoamers(such as SURFYNOL® DF110L, PC, MD-20, and DF-70); non-siliconesurfactants (anionic or nonionic) such as SURFYNOL® (Air Products)surfactants including SURFYNOL® 440 and 465 surfactants, TERGITOL®surfactants (Union Carbide), and various fluorinated surfactantsavailable from DuPont such as CAPSTONE® FS-35 fluorinated surfactant;light stabilizers available under the trademarks TINUVIN® (Ciba) andIRGANOX® (Ciba); as well as other additives described in Col. 17 (lines11-36) of U.S. Pat. No. 8,455,570 (noted above). Examples of usefulnon-silicone surfactants are also described in [0065]-[0066] of U.S.Patent Application Publication 2008/0207811 (noted above).

While not essential, it is sometimes desirable to enhance thesensitivity of some reactive polymers to longer wavelengths (forexample, at least 250 nm and up to and including 700 nm, or at least 250nm and up to and including 450 nm) by including one or morephotosensitizers including triplet state photosensitizers. A variety ofphotosensitizers are known in the art such as benzothiazole andnaphthothiazole compounds as described in U.S. Pat. No. 2,732,301(Robertson et al.), aromatic ketones as described in U.S. Pat. No.4,507,497 (Reilly, Jr.), and ketocoumarins, as described for example inU.S. Pat. No. 4,147,552 (Specht et al.) and U.S. Pat. No. 5,455,143(Ali), the disclosures of all of which are incorporated herein byreference. Particularly useful photosensitizers for long UV and visiblelight sensitivity include but are not limited to,2-[bis(2-furoyl)methylene]-1-methyl-naphtho[1,2-d]thiazoline,2-benzoylmethylene-1-methyl-3-naphthothiazoline,3,3′-carbonylbis(5,7-diethoxycoumarin),3-(7-methoxy-3-coumarinoyl)-1-methylpyridinium fluorosulfate,3-(7-methoxy-3-coumarinoyl)-1-methylpyridinium 4-toluenesulfonic acid,and 3-(7-methoxy-3-coumarinoyl)-1-methylpyridinium tetrafluoroborate.Other useful compounds are described in Columns 6 and 7 of U.S. Pat. No.4,147,552 (noted above) which compound disclosure is incorporated hereinby reference. Thioxanthones are also particularly useful for sensitizingthe type (iv) [2+2] photocycloaddition groups such as dimethylmaleimide.

One or more photosensitizers can be present in an ink jettable andUV-curable composition in an amount of at least 0.1 weight % and up toand including 5 weight %, or more likely at least 0.5 weight % and up toand including 2 weight %, based on the total weight of the ink jettableand UV-curable composition.

It is also possible to include one or more anionic polyetherpolyurethanes in the ink jettable and UV-curable compositions of thisinvention. Such materials are condensation polymers prepared usingsuitable compounds (“monomers”) having at least two hydroxyl groups (forexample, diols or triols) and compounds (“monomers”) having at least twoisocyanates groups (such as diisocyanates and triisocyanates), whichcondensation polymers have suitable acidic groups to provide the desiredacid number of the resulting polymer. The acidic groups are desirablycarboxylic acid groups but any type of acidic group can be used ifdesired. Suitable compounds having sufficient hydroxyl groups andcompounds having sufficient isocyanate groups are well known in the art,and any of these compounds can be substituted with one or more suitableacidic groups such as carboxylic acid groups. Not all of such compounds,however, need be substituted with the anionic groups. Such anionicpolyether polyurethanes are therefore generally dispersible within theaqueous colorless ink jet ink compositions without the need for separatedispersing agents (“dispersants”).

The useful anionic polyether polyurethanes can also comprise recurringunits derived from monomers that do not contain acidic groups but canhave multiple hydroxyl groups are often known as polyol or polyhydroxylderivatives of polyethers.

The anionic polyether polyurethanes generally can have a molecularweight (M_(w)) of at least 10,000 Daltons and up to and including 30,000Daltons or at least 15,000 Daltons and up to and including 25,000Daltons.

For example, particularly useful polyether polyurethanes areindividually represented by the following Structure (I):

wherein R₁ is the central portion of recurring units derived from apolyisocyanate, R² represents a recurring unit derived from a polyetherand having a molecular weight of at least 250 and up to and including2900, R³ represents a central portion of a recurring unit containing anacidic group, and X and Y can be the same or different and are oxygen ornitrogen as long as at least one of X and Y is oxygen.

For example, R₁ can be a divalent, substituted or unsubstitutedhydrocarbon group including divalent hydrocarbon groups comprising 1 to20 carbon atoms in the chain and one or more unsubstituted orsubstituted alicyclic, aliphatic, or aromatic groups, for example, suchdivalent groups as substituted or unsubstituted1,4-arylene-methylene-1,4-arylene, substituted or unsubstituted1,4-cyclohexylene-methylene-1,4-cyclohexylene, substituted orunsubstituted n-hexylene, and substituted or unsubstituted5-methyl-4,4-dimethyl-2,5-hexylene-methylene.

In Structure (I), R² can be a prepolymer comprising ethylene oxide,propylene oxide, tetramethylene oxide, or a mixture thereof that can beintroduced into the polyurethane using any suitable polyol. For example,the polyether segment can be introduced into the polyurethane backboneby using a prepolymer with both ends terminated with a hydroxyl (diol)or an amino (diamine) group. Such prepolymers are known as polyols andpolyamines. Useful polyether diols and diamines are sold under thetradenames TERATHANE® (Dupont) and JEFFAMINE®, for example the D, ED,and M series (Huntsman). Another useful polyether diamine is apolytetrahydrofuran bis(3-aminopropyl) terminated having a molecularweight of about 1,000. Mixtures of these various reactants can be usedif desired.

In Structure (I), R₃ can be obtained from polyols comprising phospho,carboxy, or sulfo groups, or a mixture of such groups. Polyolscomprising carboxy groups include but are not limited to,2,2′-bis(hydroxymethyl)propionic acid, 2,2′-bis(hydroxymethyl)butanoicacid, and hydroxyether of 2,4′-bis(1-hydroxyphenyl)valeric acid.Mixtures of these polyols can be used if desired.

Useful water-soluble or water-dispersible anionic polyetherpolyurethanes can be prepared by preparing prepolymers having arelatively low molecular weight and small excess of isocyanate groupsand chain-extending with a chain extender the prepolymers into highmolecular weight polyurethane during the dispersion process. Moredetails about the manufacturing process are described for example in[0045]-[0049] of U.S. Patent Application Publication 2008/0207811 (notedabove) the disclosure of which is incorporated herein by reference.

The acidic groups in the anionic polyether polyurethanes useful in thisinvention can be at least partially neutralized (converted into salts)using monovalent inorganic bases such as alkaline metal hydroxides. Upto 100% of the acid groups can be so neutralized.

Anionic acrylic polymers and anionic styrene-acrylic polymers can alsobe included within the ink jettable and UV-curable compositions of thepresent invention are generally water-soluble or water-dispersible dueto the presence of anionic groups distributed throughout the polymericbackbone. Such water-solubilizing anionic groups can include sulfonicacids and carboxylic acids. The term “water-soluble” is meant hereinthat when the anionic acrylic polymer or anionic styrene-acrylic polymeris dissolved in water and when such polymer is at least partiallyneutralized with an inorganic monovalent base, the resultant solution isvisually clear.

Ethylenically unsaturated polymerizable monomers (“monomers”) useful formaking useful anionic acrylic polymers include but are not limited to,methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylacrylate, butyl acrylate, hexyl acrylate, n-octyl acrylate, laurylmethacrylate, 2-ethylhexyl methacrylate, nonyl acrylate, benzylmethacrylate, 2-hydroxypropyl methacrylate, acrylonitrile,methacrylonitrile, vinyl acetate, vinyl propionate, vinylidene chloride,vinyl chloride, butadiene, isoprene, N,N-dimethyl acrylamide, acrylicacid, methacrylic acid, chloromethacrylic acid, maleic acid, andderivatives thereof. Other useful ethylenically unsaturatedpolymerizable monomers include allyl compounds such as allyl esters,vinyl ethers, vinyl esters, vinyl heterocyclic compounds, sodium styrenesulfonate, crotonic acids, vinyl ketones, olefins, itaconic acids andesters, and many other compounds that are described in [0055] of U.S.Patent Application Publication 2008/0207811 (noted above) and thedisclosure of which is incorporated herein by reference. The anionicacrylic polymers can comprise recurring units derived from the one ormore of the noted monomers that are arranged in blocks or in randomfashion along the polymer backbone.

The anionic styrene-acrylic polymers can be derived from at least one ormore acrylic monomers (as described above) and at least one or morestyrene monomers (including styrene and derivatives thereof) andoptionally others that would be readily apparent to one skilled in theart. Such anionic styrene-acrylic polymers can include blocks of thesame recurring units or have randomly occurring recurring units, derivedfrom the various ethylenically unsaturated polymerizable monomers.

The water-soluble or water-dispersible anionic acrylic polymers andstyrene-acrylic polymers can have a weight average molecular weight(M_(w)) of at least 1,000 Daltons up to and including 100,000 Daltons ortypically of at least 1,000 Daltons and up to and including 50,000Daltons. In some embodiments, the molecular weight can be at least 1500Daltons and up to and including 20,000 Daltons. In some otherembodiments, mixtures of anionic acrylic polymers and styrene-acrylicpolymers can be used in which at least one anionic acrylic polymer oranionic styrene-acrylic polymer has a molecular weight of less than orequal to 10,000 Daltons and at least one other anionic acrylic polymeror anionic styrene-acrylic polymer has a molecular weight greater than10,000 Daltons.

The anionic acrylic polymers and anionic styrene-acrylic polymers can beprepared using emulsion polymerization, solution polymerization, or bulkpolymerization techniques that are well known in the art. In addition,the acidic groups in such polymers can be at least partially neutralizedin a manner like neutralization of the anionic polyether polyurethanesdescribed above. Moreover, inorganic bases are desirable over organicbases such as amines as neutralizing agents.

Representative anionic acrylic polymers and anionic styrene-acrylicpolymers useful in the present invention are described in U.S. Pat. No.6,866,379 (Yau et al.), the disclosure of which is incorporated hereinby reference.

Such anionic polymers can be derived from at least one (meth)acrylicacid ester, with or without one or more styrenes. Any of these monomerscan be substituted with suitable acidic groups such as carboxylic acidgroups. Useful anionic polymers are described for example in [0061] ofU.S. Patent Application Publication 2008/207811 (noted above) thedisclosure of which is incorporated herein by reference.

Examples of useful anionic styrene-acrylic polymers include thosecommercially available under the trademarks JONCRYL® (S.C. Johnson Co.),TRUDOT® (Mead Westvaco Co.), and VANCRYL® (Air Products and Chemicals,Co.).

An aqueous medium such as water is generally present in the ink jettableand UV-curable compositions in an amount of at least 75 weight % or ofat least 85 weight %, and generally no more than 95 weight %, based onthe total weight of the ink jettable and UV-curable composition.

The pH of the ink jettable and UV-curable compositions of this inventioncan be adjusted if desired to at least 6 and up to and including 12, ormore likely of at least 6 and up to and including 10, or in someembodiments of at least 6 and up to and including 9.5. The pH can beachieved using any suitable base such as an alkali metal hydroxide or anorganic amine in a suitable amount.

Alkali metal hydroxides are known to provide improved ink jettingperformance in thermal ejector print heads. Buffers can be included tomaintain the desired pH and such materials would be readily apparent toone skilled in the art, including those described in Cols. 17-19 of U.S.Pat. No. 8,455,570 (noted above).

Metal-Containing Compositions

The ink jettable and UV-curable compositions described above can beconverted to corresponding metal-containing compositions described belowthat are also ink jettable and UV-curable compositions. Suchmetal-containing compositions can be incorporated into the variousarticles described below or used in various methods as described below.

Each metal-containing composition described herein has these essentialcomponents: one or more reactive polymers (or crosslinked reactedpolymers) as described above that are complexed with either reduciblemetal ions or reduced metal nanoparticles, and an optional components asdescribed above. The reactive polymers can be used to form crosslinkedreacted polymers (thus rendered water-insoluble) upon exposure toradiation having max of at least 150 nm and up to and including 700 nm,or of at least 250 nm and up to and including 450 nm, as describedbelow. While various other optional components can be included asdescribed above, only the complex of reactive polymer and eitherreducible metal ions or metal nanoparticles are essential for providingthe desired compositions, articles, and methods.

Useful reducible metals or metal nanoparticles can be composed of forexample, silver, copper, palladium, platinum, gold, nickel or tinmetals. Particularly useful metals are silver, copper, and palladium.

Several embodiments of metal-containing compositions are described asfollows.

Metal-Containing Composition (A):

In one embodiment, a water-soluble, metal-containing ink jettable andUV-curable composition comprises a water-soluble complex of a reactivepolymer (as described above) with reducible metal ions, and optionallybut desirably a humectant or other optional components described above.Such a metal-containing composition can also be considered a “metalprecursor” composition that eventually can be used to provide metalnanoparticles within a polymeric complex.

One or more complexes of reactive polymers and reducible metal ions asdescribed herein are generally present in metal-containing composition(A) (and in a resulting dry layer) in an amount of at least 10 weight %and up to and including 99 weight %, or typically at least 50 weight %and up to and including 90 weight %, based on the total solids inmetal-containing composition (A). If present, the amount of one or moreoptional components can be determined from the teaching concerningamounts shown above.

The water-soluble complexes of metal ions (non-reduced elemental metal)and reactive polymers for metal-containing composition (A) can beprepared by adding a water-soluble metal salt that would be readilyapparent to one skilled in the art. For example, reducible silver ionscan be provided by adding silver nitrate or silver acetate to an aqueoussolution of a reactive polymer with stirring and for example, usingcontrolled addition rates. Useful copper salts would also be similarlyuseful to provide complexes with reducible copper ions. Reduciblepalladium ions can be added as a water-soluble palladium chloridecomplex with acetonitrile. The reducible metal ions will tend to bindwith the sulfonate or sulfonic acid groups and optional carboxylic acidor carboxylate sites in the reactive polymer forming a metal-containingpolymer complex or salt that is less soluble and more stable than theoriginal metal salt but is still soluble in water. This metal-containingcomposition (A) containing unreduced form of the metal polymer complexcan be printed onto a suitable substrate and hardened or patterned usingultraviolet radiation. The reducible metal ions (for example reduciblesilver ions) in the ink solution or UV-cured printed images can bereduced to form metal nanoparticles (for example silver nanoparticles)by contact (such as immersion) with a reducing agent as described below,or for some metals such as silver, simply by exposure to UV or visibleradiation and heat that can cause poor long-term stability. Oxidantssuch as iodate salts can be added to the formulation to reduce oreliminate the formation of reduced metal (such as reduced silver) due toambient light and heat.

In the case of some metals such as silver and gold, the spontaneousformation of reduced metal nanoparticles using a reducing agent isobservable because of the appearance of a strong color in the visibleregion of the electromagnetic spectrum due to the surface plasmonresonance of the reduced metal nanoparticles in the resultingwater-insoluble complex.

Metal-Containing Composition (B):

In another embodiment, a metal-containing ink jettable and UV-curablecomposition comprises a water-soluble complex of a reactive polymer (asdescribed above) with metal nanoparticles (such as silvernanoparticles), and optionally but desirably a humectant or otheroptional components. Such metal-containing ink jettable and UV-curablecompositions can be readily obtained, for example, by reducing thereducible metal ions in a metal-containing composition (A) describedabove. For example, this metal-containing ink jettable and UV-curablecomposition can be obtained, for example, by reducing the silver ions ina water-soluble, silver-containing composition (A) described above.

One or more complexes of reactive polymers and metal nanoparticles asdescribed herein are generally present in metal-containing composition(B) (and in a resulting dry layer) in an amount of at least 10 weight %and up to and including 99 weight %, or typically at least 50 weight %and up to and including 90 weight %, based on the total solids inmetal-containing composition (B).

As noted above, the water-soluble complexes of metal nanoparticles (suchas silver nanoparticles) and reactive polymers for metal-containingcomposition (B) can be prepared by reducing the metal ions inmetal-containing composition (A) containing the same reactive polymer.For example, starting with a metal-containing composition (A), the rapidformation of a complex of reactive polymer and metal nanoparticles iseasily accomplished by the careful addition of a metal ion reducingagent, for example a silver ion reducing agent such as dimethylamineborane (DMAB) that is especially well suited to work at the inherent lowpH of the polymer solutions. Other silver ion reducing agents areborohydrides (for example, sodium borohydride), hydrazine, hypophosphite(such as sodium hypophosphite), amines (such astetramethylethylenediamine), aldehydes, and sugars that can be used forthis purpose if the pH of the composition is properly adjusted.

Depending on the composition of the reactive polymer and formulationconditions for certain embodiments, metal nanoparticles having anaverage diameter of at least 2 nm and up to and including 500 nm, or atleast 5 nm and up to and including 300 nm can be formed and stablydispersed and complexed within the reactive polymer such that they canbe filtered without removing the metal nanoparticles and themetal-containing composition (B) can be coated without formingparticulate defects. The resulting complex of reactive polymer and metalnanoparticles can be strongly colored, especially for small particleswith a narrow size distribution due to the strong surface plasmonresonance effect. The complex of reactive polymer and metalnanoparticles can again be dialyzed if necessary to remove any reactionproducts or salts produced as by-products during the formation of thecomplex.

Alternatively, metal-containing composition (B) can be prepared bymixing metal nanoparticles from any commercial source to an aqueoussolution of a reactive polymer with stirring until complexation occurs,and optionally including a humectant. The metal nanoparticles will tendto bind with the sulfonate or sulfonic acid groups and optionalcarboxylic acid or carboxylate sites in the reactive polymer forming ametal nanoparticle-polymer complex.

Metal-Containing Composition (C):

Yet another useful embodiment comprises a crosslinked water-insolublemetal-containing composition of a crosslinked reacted polymer withreducible metal ions and optionally but desirably optional componentssuch as a humectant. Such crosslinked reacted polymer can be derivedfrom suitable photoexposure of an ink jettable UV-curable compositioncomprising a reactive polymer (as described above) that is complexedwith reducible metal ions. Such metal-containing composition can beobtained, for example, by photoexposure of water-soluble,metal-containing composition (A) described above but before anyappreciable metal ion reduction occurs. Alternatively, one can crosslinka reactive polymer as described herein in an ink jettable and UV-curablecomposition and then imbibe or diffuse metal ions into it forcomplexation with the sulfonic acid and any carboxylic acid groups inthe reacted polymer.

Metal-Containing Composition (D):

Still another useful embodiment comprises a crosslinked metal-containingcomposition comprising a crosslinked water-insoluble complex of acrosslinked reacted polymer with metal nanoparticles and optionally butdesirably including optional components such as a humectant. Suchcrosslinked reacted polymer can be derived from photoexposure asdescribed herein of an ink jettable and UV-curable compositioncomprising a reactive polymer (as described above) that is alreadycomplexed with metal nanoparticles (such as silver nanoparticles) fromappropriate reduction of reducible metal ions. This crosslinkedcomposition can be derived for example, by photoexposure ofmetal-containing ink jettable and UV-curable composition (B) describedabove; by both photoexposure and metal ion reduction, in any order, ofcomposition (A) described above; or by metal ion reduction ofmetal-containing composition (C) described above.

In some embodiments, the resulting metal nanoparticles (such as silvernanoparticles) can have an average diameter of at least 2 nm and up toand including 500 nm, or at least 6 nm and up to and including 300 nmsuch that they can be formed and stably dispersed and complexed withinthe reactive polymer so that they can be filtered without removing themetal nanoparticles and the metal-containing composition (D) can becoated without forming particulate defects.

Alternatively, one can diffuse a non-complexed solution of metalnanoparticles such as silver nanoparticles into the crosslinked reactivepolymer where the silver nanoparticles will preferentially bind orcomplex with the sulfonic acid, carboxylic acid, or other groups.

Metal-containing compositions (A) through (D) generally do not includeseparate crosslinking agents or crosslinking agent precursors becausethe reactive polymer itself includes sufficient crosslinkable groups(described above).

However, as noted above, if present, the (d) recurring units can alsoinclude additional crosslinking groups.

The essential complexes of reactive polymer and either reducible metalions or metal nanoparticles and any optional components described above,are generally dissolved or dispersed in an aqueous medium such as wateror a mixture of water and water-miscible organic solvents to form ametal-containing, ink jettable and UV-curable composition that can beapplied to a suitable substrate (described below) using suitable inkjetting processes and equipment. Useful water-miscible organic solventsinclude but are not limited to, alcohols such as methanol, ethanol, andisopropanol and polyols such as ethylene glycol, propylene glycol, andglycerol. The amounts of the complexes and any optional compounds in thevarious ink jettable and UV-curable compositions can be readilydetermined by a skilled artisan for desired use for ink jetting.

Inventive Articles

The ink jettable and UV-curable compositions and metal-containingcompositions of the present invention can be used to prepare a varietyof articles that can be used for various purposes as described above,for example for antimicrobial purposes as well as for preparingelectrically-conductive elements (or articles).

In all of these articles, an ink jettable and UV-curable composition canbe disposed in a suitable ink jetting process onto one or multiplesurfaces of a suitable substrate. Some useful ink jetting processes andequipment are described below.

Useful substrates can be chosen for a particular use or method as longas the substrate material will not be degraded by the ink jettable andUV-curable composition or any treatments to which the resulting articlesare subjected during the method described below. The ink jettable andUV-curable composition can be applied multiple times if desired toobtain a thicker coating, and dried between each coating or dried onlyafter the last application. Water and any water-miscible organicsolvents can be removed from the ink jettable and UV-curable compositionusing any suitable drying technique.

In general, the final dry image of an ink jettable and UV-curablecomposition can have an average dry thickness of at least 10 nm and upto and including 1 mm, with a dry thickness of at least 0.1 μm and up toand including 100 μm being useful for various uses. Such images can beuniformly applied on a substrate surface or applied in a suitablepatternwise fashion as described below.

Useful substrates can be composed of glass, quartz, and ceramics as wellas a wide variety of flexible materials such as cellulosic papers andpolymeric films composed of polyesters including poly(ethyleneterephthalate) and poly(ethylene naphthalate), polycarbonates,polyamides, polyimides, poly(meth)acrylates, or polyolefins. Usefulpolymeric substrates can be formed by casting or extrusion methods.Laminates of various substrate materials can also be put together toform a composite substrate. Any of the substrates can be treated toimprove adhesion using for example corona discharge, oxygen plasma,ozone or chemical treatments using silane compounds such asaminopropyltriethoxysilane. The substrates can be of any suitable drythickness including but not limited to at least 10 μm and up to andincluding 10 mm, depending upon the intended use of the resultingarticles.

Particularly useful substrates are flexible substrates that are composedof poly(ethylene terephthalate) such as biaxially oriented poly(ethyleneterephthalate) (PET) films. These PET films, ranging in dry thickness ofat least 50 μm and up to and including 200 μm, can also comprise, on atleast one supporting side, a polymeric primer layer (also known as asubbing layer, adhesive layer, or binder layer) that can be added priorto or after film stretching. Such polymeric primer layers can comprisepoly(acrylonitrile-co-vinylidene chloride-co-acrylic acid), poly(methylacrylate-co-vinylidene chloride-co-itaconic acid), poly(glycidylmethacrylate-co-butyl acrylate), or various water-dispersiblepolyesters, water-dispersible polyurethanes, or water-dispersiblepolyacrylics, as well as sub-micrometer silica particles. The drythickness of the primer layer can be at least 0.1 μm and up to andincluding 1 μm.

In many embodiments of the present invention, each of the substrates canhave an integrated transmittance of at least 80%, or at least 90% oreven higher to provide articles that have excellent transparency. Suchhighly transparent substrates can be composed of glass (such as flexibleglass) or flexible polymeric films as described above.

The useful substrates can be in any suitable shape or size. They can bein the form of sheets, films, tubes, particles, or various 3-dimensionalshapes depending upon the intended use. Some particularly usefulsubstrates are in the form of continuous flexible webs or films that canbe unrolled from a stock roll, ink jet printed to apply an ink jettableand UV-curable composition followed by other treatments and then rolledup for shipment or later use in roll-to-roll manufacturing processes.

If a substrate is in the form of a sheet or roll, it typically has twoopposing planar surfaces known herein as a “first supporting surface”and an “opposing second supporting surface”. An ink jettable andUV-curable composition can be ink jetted onto one or both supportingsurfaces of the substrate such as only on the first supporting side, orthe same or different ink jettable and UV-curable composition (such as asilver or copper-containing ink jettable and UV-curable composition) canbe disposed on both the first supporting surface and the opposing secondsupporting surface of the substrate.

In some embodiments, a precursor article can be prepared with asubstrate and having an ink jettable and UV-curable composition [forexample metal-containing composition (A) as described above] ink jetprinted onto the substrate, for example on one or both supportingsurfaces of a sheet or continuous flexible web. In some embodiments,such precursor composition can comprise a water-soluble complex of areactive polymer (as described above) with reducible silver ions andoptional components described below.

In other embodiments, a precursor metal ion-containing article cancomprise a substrate and have ink jet printed thereon (for example, in apatternwise fashion) a water-insoluble (crosslinked) metal-containingcomposition [for example, metal-containing composition (D) as describedabove], comprising a crosslinked water-insoluble complex of acrosslinked reacted polymer with reducible metal ions, and optionalcomponents. Such crosslinked reacted polymer can be derived byphotoexposure of a reactive polymer as described above. Suchwater-insoluble (crosslinked) metal-containing composition can be inkjet printed onto only the first supporting surface of the substrate, butin other embodiments, the same or different water-insoluble complex canbe ink jet printed onto both the first supporting surface and theopposing second supporting surface of the substrate. In still otherembodiments, the same or different water-insoluble (crosslinked)metal-containing composition is ink jet printed onto both the firstsupporting surface and the opposing second supporting surface of thesubstrate in the same or different patternwise fashion (using meansdescribed below).

It is also possible to prepare precursor metal-containing articles thatcomprise a substrate and having ink jet printed thereon a water-solublemetal-containing composition [for example, a silver-containingcomposition (B) described above] comprising a water-soluble complex of areactive polymer (described above) with metal nanoparticles andoptionally a humectant. Such water-soluble metal-containing compositioncan be ink jet printed on only the first supporting surface of thesubstrate, but in other embodiments, the same or different water-solublecomplex can be ink jet printed on both the first supporting surface andthe opposing second supporting surface of the substrate. In still otherembodiments, the same or different water-soluble complex is ink jetprinted on both the first supporting surface and the opposing secondsupporting surface of the substrate in the same or different patternwisefashion. Such precursor metal-containing articles can also comprise asuitable photosensitizer (as described above) admixed with thewater-soluble complex and optional components.

In still other embodiments, a metal-containing article can comprise asubstrate and having ink jet printed thereon a water-insolublemetal-containing composition [for example, a silver-containingcomposition (C) described above] comprising a crosslinkedwater-insoluble complex of a crosslinked reacted polymer with metalnanoparticles. This crosslinked reacted polymer can be derived fromphotoexposure of a reactive polymer as described above. Suchwater-insoluble (crosslinked) metal-containing composition can be inkjet printed onto only the first supporting surface of the substrate, butin other embodiments, the same or different water-insoluble complex canbe ink jet printed on both the first supporting surface and the opposingsecond supporting surface of the substrate. In still other embodiments,the same or different water-insoluble (crosslinked) metal-containingcomposition is ink jet printed onto both the first supporting surfaceand the opposing second supporting surface of the substrate in the sameor different patternwise fashion (using means described below).

As prepared using conditions described in more detail below, themetal-containing article can further comprise an electrically-conductivemetal that has been electrolessly plated on the same or differentcrosslinked water-insoluble complex ink jet printed on both the firstsupporting surface and the opposing second supporting surface of thesubstrate. This electrically-conductive metal is typically electrolesslyplated on the crosslinked water-insoluble complex in which the metalnanoparticles (such as silver or palladium nanoparticles) serve ascatalyst seed metal particles. For example, the electrolessly platedmetal can be copper, silver, gold, platinum, palladium, nickel, oranother metal that can be catalyzed by the catalytic metalnanoparticles.

The crosslinked water-insoluble complex can be ink jet printed on thesubstrate in a patternwise fashion, and the metal-containing article canfurther comprise an electrically-conductive metal that has beenelectrolessly plated on the crosslinked water-insoluble complex in thesame patternwise fashion so that only the pattern of the water-insolublecomplex is electrolessly plated.

Methods for Making and Using Articles

The present invention can be used in various methods for providingarticles as described above. For example, precursor articles describedabove can be prepared by ink jet printing a metal-containing composition(as described above) onto a suitable substrate (as described above). Themetal-containing composition comprises a water-soluble complex of areactive polymer (as described above) with reducible metal ions. Themetal-containing composition can be ink jet printed in any suitablemanner with suitable equipment as described below in a patternwisefashion to provide any desired predetermined or random pattern on asupporting surface.

It may also be possible to use the present invention to provide certainspecifically designed patterns for optimal non-toxic bioadhesion controlso that marine organisms are less likely to foul or adhere to theresulting article in which the reducible metal ions (such as silverions) have been reduced to metal nanoparticles (such as silvernanoparticles). Some of such patterns are sometimes identified asSharklet™ patterns as described in U.S. Patent Application Publication2010/0226943A1 (Brennan et al.), the disclosure of which is incorporatedherein by reference.

The ink jettable and UV-curable compositions described herein can be inkjet printed onto a substrate using suitable ink jet printing processesand equipment.

In most embodiments, the ink jet printed image is provided by ink jetprinting an ink jettable and UV-curable composition using thermal orpiezoelectric drop-on-demand (DOD) printheads and continuous (CIJ)printheads that utilize electrostatic charging devices and deflectorplates. Each type of printhead and apparatus attached thereto requirespecific properties in the ink jettable and UV-curable composition inorder to achieve reliable and accurate jetting.

For example, in many embodiments, the ink jettable and UV-curablecomposition has a dedicated delivery channel.

When the method is carried out using CIJ apparatus and processes, itcomprises:

ink jetting the ink jettable and UV-curable composition described hereinfrom a main fluid supply as a continuous stream that is broken into boththe spaced drops and non-printing drops; and

collecting and returning the non-printing drops to the main fluidsupply.

For all of the ink jetting operations and particularly for ink jettingthe ink jettable and UV-curable composition, ink jetting can be carriedout at a suitable firing frequency of at least 350 kHz with a nearnozzle velocity of at least m/sec (a thermal print head would be 10 kHzand about 10 m/sec velocity).

The ink jettable and UV-curable composition can be positioned in any oneof the printhead ports intended for use in the present invention.Multiple ink jettable and UV-curable compositions can be positioned onthe same carriage assembly, or each can be positioned on a separatecarriage assembly in the ink jet printing apparatus.

In other embodiments, a method is used to provide an article comprisingmetal nanoparticles such as silver nanoparticles or palladiumnanoparticles. This method comprises, firstly inkjet printing ametal-containing composition (containing reducible metal ions asdescribed above) onto either or both supporting surfaces of a suitablesubstrate (as described above). If the metal-containing composition iscomposed of reducible metal ions, they can be reduced after disposingthe metal-containing composition onto the substrate and UV-curing toform a water-insoluble pattern. The reducible metal ions in thewater-soluble complex are then reduced (using chemistry described below)to form metal nanoparticles (for example, having an average diameterdescribed above, for example at least 2 nm and up to and including 500nm) in the water-soluble complex. For example, reducible silver ions canbe reduced using an aqueous solution of dimethylborane, a borohydride, ahypophosphite, an amine, an aldehyde, or a sugar. If a metal-containingis composed of metal nanoparticles formed by reducing the metalion-containing composition before disposing it onto a substrate, theresulting article can be stored for later use if desired, but in manyembodiments, the water-soluble complex containing the metalnanoparticles is photoexposed using conditions described below (forexample, using ultraviolet radiation having a λ_(max) of at least 150nm) to form an ink jet printed, crosslinked, water-insoluble complexcomprising the metal nanoparticles on one or both supporting surfaces ofthe substrate.

In some embodiments, this method further comprises, after photoexposingthe water-soluble complex to form the crosslinked water-insolublecomplex containing metal nanoparticles,

heating the crosslinked water-insoluble complex containing metalnanoparticles at a temperature sufficient to further crosslink thecrosslinked water-insoluble complex containing the metal nanoparticles.Conditions for this heating treatment are described below.

The crosslinked, water-insoluble complex containing metal nanoparticles,on either or both supporting surfaces of the substrate, can beelectrolessly plated using an electrically-conductive metal usingsolutions and conditions as described in more detail below.

Thus, in some useful embodiments, the method can comprise:

providing a substrate,

ink jetting an ink jettable and UV-curable composition (as describedabove) onto the substrate in an imagewise fashion to form an ink jettedimage on the substrate, and

UV-curing the ink jetted image to form a UV-cured ink jetted image onthe substrate.

This method can be continued by:

contacting the UV-cured ink jet image with reducible metal ions or metalnanoparticles to form a UV-cured metallized image on the substrate,

if the UV-cured metallized image comprises reducible metal ions,contacting the UV-cured metallized image with a metal ion reducingagent, and

optionally, electrolessly plating the UV-cured metallized image on thesubstrate.

For example, in such methods, a metal-containing composition can be inkjet printed onto one or both supporting surfaces of the substrate in apatternwise fashion.

In some particularly useful embodiments, the compositions of the presentinvention can be used to prepare electrically-conductive patterns onboth supporting surfaces of a flexible continuous web, such as acontinuous (roll) of polymeric substrate, for example in a roll-to-rollmanufacturing operation. Thus, in such embodiments, the method forproviding a “dual-sided” article, comprising ink jet printing ametal-containing composition (as described above) onto at least a firstsupporting surface of a suitable substrate (such as a continuous web).After ink jet printing the metal-containing composition onto the firstsupporting surface of the substrate, and UV-curing the printedcomposition, the reducible metal ions in the UV-cured complex can bereduced to form metal nanoparticles in the water-soluble complex on thefirst supporting surface of the substrate using the reducing conditionsand solutions described below. The same or different metal-containingcomposition can then be disposed in a suitable fashion onto an opposingsecond supporting surface of the same substrate, and after UV-curing themetal-containing composition on the opposing second supporting surfaceof the substrate, the reducible metal ions in the water-soluble complexcan be reduced to form metal nanoparticles in the water-soluble complexon the opposing second supporting surface of the substrate. It is alsopossible to remove any remaining water-soluble complex from both thefirst supporting surface and the opposing second supporting surface ofthe substrate.

In many of such embodiments, the method further comprises:

electrolessly plating the crosslinked water-insoluble complex on eitheror both of the first supporting surface and the second opposingsupporting surface of the substrate using an electrically-conductivemetal (using electrolessly plating solutions and conditions describedbelow).

In such embodiments, the method can also comprise:

photoexposing the water-soluble complex containing the metalnanoparticles on either or both of the first supporting surface and theopposing second supporting surface in a patternwise fashion on thesubstrate.

Photoexposing of the water-soluble complex can be carried out usingultraviolet radiation having λ_(max) of at least 150 nm.

After such features, the method can further comprise, afterphotoexposing the water-soluble complex on either or both of the firstsupporting surface and the opposing second supporting surface of thesubstrate to form the crosslinked water-insoluble complex containingmetal nanoparticles,

heating the crosslinked water-insoluble complex containing metalnanoparticles on either or both of the first supporting surface and theopposing second supporting surface of the substrate at a temperaturesufficient to further crosslink the crosslinked water-insoluble complexcontaining the metal nanoparticles.

The reducing feature can be carried out on both supporting surfaces ofthe substrate using an aqueous solution for example containingdimethylamine borane, a borohydride, a hypophosphite, an amine, analdehyde, or a sugar, when the reducible metal ions are reducible silverions.

The following discussion provides some details about representativeelectroless plating methods.

In electroless plating methods, each aqueous-based “processing”solution, dispersion, or bath (for example, solutions containingelectroless seed metal ions, reducing agent solutions, and solutions forelectroless plating, as well as rinsing solutions) used at variouspoints can be specifically designed with essential components as well asoptional addenda readily apparent to one skilled in the art. Forexample, one or more of those aqueous-based processing solutions caninclude such addenda as surfactants, anti-coagulants, anti-corrosionagents, anti-foamants, buffers, pH modifiers, biocides, fungicides, andpreservatives. The aqueous-based reducing solutions can also includesuitable antioxidants.

Exposure of the ink jetted images can be carried out using radiationhaving a λ_(max) of at least 150 nm and up to and including 700 nm or toradiation having a λ_(max) of at least 250 nm and up to and including450 nm. This exposure can be provided with any suitable exposing sourceor device that provides the desired radiation including but not limitedto, various arc lamps and LED sources. The particular exposing sourcecan be chosen depending upon the absorption characteristics of the inkjettable and UV-curable composition used. Exposure time can range from afraction (0.1) of a second and up to and including 10 minutes dependingupon the intensity of the radiation source and the ink jettable andUV-curable composition.

It is optional but desirable to heat or bake an article simultaneouslywith or after the exposure at a temperature sufficient to furthercrosslink the at least partially crosslinked reacted polymer. Suchheating can be accomplished on a hot plate with vacuum suction to holdthe article in close contact with the heating surface. Alternatively,the heating device can be a convection oven. The duration of the heatingprocedure is generally less than 10 minutes with heating for least 10seconds and up to and including 5 minutes being most likely. The optimalheating time and temperature can be readily determined with routineexperimentation.

Reduction of the reducible metal ions at a suitable time can be done bycontacting the complex containing such reducible metal ions with asuitable reducing agent for the metal ions, for example by immersionwithin an aqueous-based reducing solution containing one or morereducing agents for a suitable time to cause sufficient metal ionreduction to metal nanoparticles. Alternatively, an aqueous-basedreducing solution comprising the reducing agent can be sprayed or rolleduniformly onto an ink jet printed image containing the reducible metalions.

For reducible silver ions, useful reducing agents include but are notlimited to, an organic borane, an aldehyde such as formaldehyde,aldehyde sugar, hydroquinone, or sugar (or polysaccharide) such asascorbic acid, and metal ions such as tin(II). These reducing agents canbe used individually or in combination, and the total amount in theaqueous-based reducing solution used for the reducing procedure can beat least 0.01 weight % and up to and including 20 weight % based on thetotal reducing solution weight. The amount of reducing agent to be usedwill depend upon the reducing agent to be used and this can be readilyoptimized using routine experimentation. The time and temperature forthe reduction can also be readily optimized in the same manner.Generally, the reducing temperature is at least room temperature (about20° C.) and up to and including 95° C. and the reducing time can be forat least 1 second and up to and including 30 minutes.

For example, some embodiments using reducible silver ions can be carriedout using an immersion bath comprising 1 reducing solution weight % ofan organic borane such as dimethylamine borane (DMAB) at roomtemperature for up to 3 minutes. Longer or shorter times at highertemperatures are possible if needed.

After a reducing procedure, the complex containing the metalnanoparticles can be washed using distilled water or deionized water oranother aqueous-based solution at a suitable temperature for a suitabletime.

The resulting article can be immediately immersed in an aqueous-basedelectroless metal plating bath or solution, or the article can be storedwith just the catalytic pattern comprising the metal nanoparticles aselectroless seed metal particles for use at a later time.

For example, the article containing catalytic metal nanoparticles in thecrosslinked, water-insoluble complex can be contacted with anelectroless plating metal that is the same as or different from thecatalytic electroless seed metal nanoparticles. In most embodiments, theelectroless plating metal is a different metal from the catalyticelectroless seed metal nanoparticles.

Any metal that will likely electrolessly “plate” on the catalyticelectroless seed metal nanoparticles can be used at this point, but inmost embodiments, the electroless plating metal can be for examplecopper(II), silver(I), gold(IV), palladium(II), platinum(II),nickel(II), chromium(II), and combinations thereof. Copper(II),silver(I), and nickel(II) are particularly useful electroless platingmetals.

The one or more electroless plating metals can be present in theaqueous-based electroless plating bath or solution in an amount of atleast 0.01 weight % and up to and including 20 weight % based on totalsolution weight.

Electroless plating can be carried out using known temperature and timeconditions, as such conditions are well known in various textbooks andscientific literature. It is also known to include various additivessuch as metal complexing agents or stabilizing agents in theaqueous-based electroless plating solutions. Variations in time andtemperature can be used to change the metal electroless platingthickness or the metal electroless plating deposition rate.

A useful aqueous-based electroless plating solution or bath is anelectroless copper(II) plating bath that contains formaldehyde as areducing agent.

Ethylenediaminetetraacetic acid (EDTA) or salts thereof can be presentas a copper complexing agent. For example, copper electroless platingcan be carried out at room temperature for several seconds and up toseveral hours depending upon the desired deposition rate and platingrate and plating metal thickness.

Other useful aqueous-based electroless plating solutions or bathscomprise silver(I) with EDTA and sodium tartrate, silver(I) with ammoniaand glucose, copper(II) with EDTA and dimethylamineborane, copper(II)with citrate and hypophosphite, nickel(II) with lactic acid, aceticacid, and a hypophosphite, and other industry standard aqueous-basedelectroless baths or solutions such as those described by Mallory et al.in Electroless Plating: Fundamentals and Applications 1990.

After the electroless plating procedure, the resulting product articlecan be removed from the aqueous-based electroless plating bath orsolution and can again be washed using distilled water or deionizedwater or another aqueous-based solution to remove any residualelectroless plating chemistry.

To change the surface of the electroless plated metal for visual ordurability reasons, it is possible that a variety of post-treatments canbe employed including surface plating of still at least another (thirdor more) metal such as nickel or silver on the electrolessly platedmetal (this procedure is sometimes known as “capping”), or the creationof a metal oxide, metal sulfide, or a metal selenide layer that isadequate to change the surface color and scattering properties withoutreducing the conductivity of the electrolessly plated (second) metal.Depending upon the metals used in the various capping procedures of themethod, it may be desirable to treat the electrolessly plated metal witha seed metal catalyst in an aqueous-based seed metal catalyst solutionto facilitate deposition of additional metals.

As one skilled in the art should appreciate, the individual treatmentfeatures or steps described above for these methods can be carried outtwo or more times before proceeding to the next procedure or step. Forexample, multiple treatments with an aqueous-based reducing solution oraqueous-based electroless metal plating solution can be carried out insequence, using the same or different conditions. Sequential washing orrinsing steps can also be carried out where appropriate.

In some embodiments, the water-soluble complexes containing the reactivepolymers can be ink jet printed on various substrates in a patternwisemanner for further chemical reactions such as providing catalytic metalnanoparticles (such as silver nanoparticles) that can then be used toform high resolution electrically-conductive metal patterns as describedherein. Such electrically-conductive metal patterns can be incorporatedinto various devices including but not limited to touch screens or otherdisplay devices that can be used in numerous industrial, consumer, andcommercial products. Thus, patterns formed from the metal-containingcompositions can be incorporated into various articles or devices.

Systems and methods of fabricating flexible and optically complianttouch sensors in a high-volume roll-to-roll manufacturing processwherein micro electrically-conductive features can be created in asingle pass are possible. The ink jettable and UV-curable compositionsof the present invention can be used to prepare such systems and methodswith one or more ink jet printing devices to form multiple highresolution electrically-conductive images. Multiple patterns can be inkjet printed on one or both supporting surfaces of a substrate. Forexample, one predetermined pattern can be ink jet printed on onesupporting surface of the substrate and a different predeterminedpattern can be ink jet printed on the opposing second supporting surfaceof the substrate that can be a continuous web.

In some embodiments, the present invention can be used to providemetal-containing articles such as silver-containing articles orcopper-containing articles that can be used for anti-fouling orantimicrobial purposes in aquatic or marine environments, or in clothingor medical devices.

The present invention provides at least the following embodiments andcombinations thereof, but other combinations of features are consideredto be within the present invention as a skilled artisan would appreciatefrom the teaching of this disclosure:

1. An ink jettable and UV-curable composition comprising:

a reactive polymer comprising: (a1) at least 20 mol % of recurring unitscomprising pendant metal complexing water-solubilizing groups, (b) atleast mol % of recurring units comprising a pendant group capable ofcrosslinking via [2+2] photocycloaddition, and optionally (c) at least 1mol % of recurring units comprising a pendant amide, hydroxyl, or lactamgroup, or a pendant precursor moiety for the pendant amide, hydroxyl, orlactam group, all amounts based on the total recurring units in thereactive polymer; and

optionally, one or more of the following components:

a humectant,

a dye or pigment colorant,

an anionic or nonionic surfactant,

a water-soluble or water-dispersible acrylic polymer, and

a water-soluble or water-dispersible polyurethane.

2. An ink jettable and UV-curable composition comprising:

a complex of reducible metal ions or metal nanoparticles with a reactivepolymer, the reactive polymer comprising: (a2) at least 5 mol % ofrecurring units comprising pendant sulfonate groups, (b) at least 5 mol% of recurring units comprising a pendant group capable of crosslinkingvia [2+2] photocycloaddition, and optionally (c) at least 1 mol % ofrecurring units comprising a pendant amide, hydroxyl, lactam group,carboxylic acid, phosphonic acid group or a pendant precursor moiety forthe pendant amide, hydroxyl, lactam, carboxylic acid, or phosphonic acidgroup, all amounts based on the total recurring units in the reactivepolymer; and

optionally, one or more of the following components:

a humectant,

a dye or pigment colorant,

an anionic or nonionic surfactant,

a water-soluble or water-dispersible acrylic polymer, and

a water-soluble or water-dispersible polyurethane.

3. The ink jettable and UV-curable composition of embodiment 1 thatcomprises a complex of reducible silver ions or silver nanoparticleswith the reactive polymer.

4. The ink jettable and UV-curable composition of embodiment 2 or 3,comprising a complex of silver nanoparticles with the reactive polymer,wherein the silver nanoparticles have an average diameter of at least 2nm and up to and including 500 nm.

5. The ink jettable and UV-curable composition of any of embodiments 2to 4, comprising a complex of silver nanoparticles with the reactivepolymer, wherein the silver nanoparticles have an aspect ratio of lessthan 2.

6. The ink jettable and UV-curable composition of any of embodiments 2to 5, comprising a complex of silver nanoparticles with the reactivepolymer, wherein the silver nanoparticles have an aspect ratio ofgreater than or equal to 2.

7. The ink jettable and UV-curable composition of embodiment 2 thatcomprises a complex of reducible palladium ions or palladiumnanoparticles with the reactive polymer.

8. The ink jettable and UV-curable composition of any of embodiments 1to 7, wherein the reactive polymer comprises at least 40 mol % of the(a1) recurring units comprising sulfonic acid or sulfonate groups, basedon the total recurring units in the reactive polymer.

9. The ink jettable and UV-curable composition of any of embodiments 1to 8, wherein the reactive polymer comprises at least 5 mol % and up toand including 50 mol % of the (b) recurring units, based on the totalrecurring units in the reactive polymer.

10. The ink jettable and UV-curable composition of any of embodiments 1to 9, wherein the reactive polymer comprises at least 1 mole % and up toand including 55 mol % of (c) recurring units comprising pendanthydroxyl, amide, or carboxylic acid groups, based on the total recurringunits in the reactive polymer.

11. The ink jettable and UV-curable composition of any of embodiments 1to 10, wherein the (b) recurring units comprise:

(i) a photosensitive —C(═O)—CR═CR¹—Y group wherein R and R¹ areindependently hydrogen or an alkyl group having 1 to 7 carbon atoms, a5- to 6-membered cycloalkyl group, an alkoxy group having 1 to 7 carbonatoms, a phenyl group, or a phenoxy group, and Y is an aryl orheteroaryl group;

(ii) a photosensitive, non-aromatic unsaturated carbocyclic group;

(iii) a photosensitive, non-aromatic heterocyclic group comprising acarbon-carbon double bond that is conjugated with an electronwithdrawing group;

(iv) a photosensitive non-aromatic unsaturated heterocyclic groupcomprising one or more amide groups that are conjugated with acarbon-carbon double bond, which photosensitive non-aromatic unsaturatedheterocyclic group is linked to the water-soluble backbone at an amidenitrogen atom, or

(v) a photosensitive substituted or unsubstituted 1,2-diarylethylenegroup.

12. The ink jettable and UV-curable composition of any of embodiments 1to 11, further comprising a humectant that is chosen from at least oneof the following groups of compounds:

(1) polyhydric alcohols;

(2) polyoxygenated polyols and their derivatives;

(3) sulfur-containing polyol compounds;

(4) cyclic lactams; and

(5) cyclic ureas.

13. The ink jettable and UV-curable composition of any of embodiments 1to 12, further comprising a pigment colorant.

14. The ink jettable and UV-curable composition of embodiment 13 furthercomprising a pigment colorant that has a median particle diameter ofless than 150 nm and more likely less than 100 nm, in an amount of atleast 0.1 weight % and up to and including 30 weight %, based on thetotal weight of the ink jettable and UV-curable composition.

15. The ink jettable and UV-curable composition of any of embodiments 1to 14, further comprising a nonionic surfactant.

16. The ink jettable and UV-curable composition of any of embodiments 1to 15, further comprising a water-soluble or water-dispersiblepolyurethane.

17. The ink jettable and UV-curable composition of any of embodiments 1to 16 having a viscosity of less than 3 centipoise as measured at 25° C.

18. The ink jettable and UV-curable composition of any of embodiments 1to 17, further comprising a photosensitizer.

The following Examples are provided to illustrate the practice of thisinvention and are not meant to be limiting in any manner.

Synthesis of 2-Cinnamoyl-Ethyl Methacrylate Monomer

Into a 500 ml, 3 neck round bottom flask equipped with a condenser andmagnetic stir bar, were added 2-hydroxyethyl methacrylate, (11.30 g,0.0868 mole) (M_(w)=130.14 g/mole), dichloromethane (DCM) (60 g), andtriethylamine (M_(w)=101.19 g/mole) (8.50 g, 0.084 mole). The reactionmixture was stirred until a homogenous solution was obtained and it wasplaced in an ice bath. A solution of cinnamoyl chloride (M_(w)=166.6g/mole) (13.33 g, 0.080 mole) dissolved in 30 g of DCM was slowly addeddropwise over the course of 15 minutes. After this addition, thereaction was allowed to come to room temperature, placed in oil bath at40° C. and refluxed for 60 minutes to complete the reaction. Thereaction mixture was then cooled and removed from the oil bath and theamine hydrochloride precipitate formed during the reaction was filteredoff. Additional DCM was added and the reaction mixture was placed into aseparatory funnel and the filtered solution was washed twice with sodiumbicarbonate, washed twice with distilled water, washed once with dilutehydrochloric acid solution, and then washed twice with distilled water.The organic layer was placed over magnesium sulfate for 30 minutes andfiltered. The DCM was removed by evaporation and the remaining productwas placed under high vacuum at room temperature overnight to remove anyresidual DCM. The final product was a clear oil with a yellow tinthaving an M_(w) of 260.29 g/mole. The purity was verified by NMR.

Synthesis of 7-(2-Methacryloyloxyethoxy)-4-methylcoumarin Monomer

15.3 g of 4-Methylumbelliferone (7-hydroxy-4-methylcourmarin) wasdissolved in about 300 ml of dimethylacetamide (DMA) in a 3-neck 1 literflask with an overhead stirrer. 48 g of Potassium carbonate, 20.8 g of2-((methylsulfonyl)oxy)ethyl methacrylate prepared from 2-hydroxyethylmethacrylate using standard procedures, and 1.66 g of potassium iodidewere then added and the reaction mixture was heated in an oil bath at70° C. about 18 hours. Thin layer chromatography was used to determinethat the reaction was complete. The reaction solution was cooled andpoured into about 1 liter of water, stirred for about an hour, and theprecipitate was filtered. The precipitate was then rinsed with another 1liter of water then heptane and dried on the filter. The desired productwas confirmed by NMR. A portion of the product was further purified bysilica gel chromatography with ethyl acetate. The ethyl acetate wasremoved by evaporation and the product was crystallized from heptane toobtain a white powder.

Preparation of Inventive Terpolymer a from Styrene Sulfonic Acid SodiumSalt, Methacrylic Acid, and 7-(2-Methacryloyloxyethoxy)-4-Methylcoumarinin a 50:30:20 Mol % Ratio

5.0 g of Styrene sulfonic acid sodium salt, 1.25 g of methacrylic acid,and 2.80 g of 7-(2-methacryloyloxyethoxy)-4-methylcoumarin were weighedout into a 250 ml single neck round bottom flask dissolved in a solventmixture of 27 g of water, 27 g of dimethylacetamide (DMA), and 27 g ofisopropyl alcohol. 0.45 g of AMBN free radical initiator was added andnitrogen was bubbled through the solvent mixture for 30 minutes beforeheating it in an oil bath at 80° C. for about 18 hours. The reactionsolution was cooled and diluted with water to form a clear solution. Thereaction solution was dialyzed for about 18 hours and then concentratedto a 15.55 weight % solids solution that was suitable for coating. Theweight average molecular weight (M_(w)) of the resulting Terpolymer Awas 48,500 as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer B from Styrene Sulfonic Acid SodiumSalt, Methacrylic Acid, and 7-(2-Methacryloyloxyethoxy)-4-Methylcoumarinin a 10:70:20 Mol % Ratio

1.25 g of Styrene sulfonic acid sodium salt, 3.65 g of methacrylic acid,and 3.50 g of 7-(2-methacryloyloxyethoxy)-4-methylcoumarin were weighedout into a 250 ml single neck round bottom flask dissolved in a solventmixture of 25 g of water, 25 g of dimethylacetamide (DMA), and 25 g ofisopropyl alcohol. 0.42 g of AMBN free radical initiator was added andnitrogen was bubbled through the solvent mixture for 30 minutes beforeheating it in an oil bath at 80° C. for about 18 hours. The reactionsolution was cooled and diluted with water to form a clear solution. Thereaction solution was dialyzed for about 18 hours and then concentratedto a 15.30 weight % solids solution that was suitable for coating. Theweight average molecular weight (M_(w)) of the resulting Terpolymer Bwas 72,400 as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer C from 3-Sulfopropyl MethacrylatePotassium Salt, Methaecrylic Acid, and 2-Cinnamoyl-Ethyl Methacrylate ina 50:30:20 Mol % Ratio

In a 500 ml single neck round bottom flask, 13.86 g of 3-sulfopropylmethacrylate potassium salt, 2.91 g of methacrylic acid, 5.85 g of2-cinnamoyl-ethyl methacrylate, and 0.566 g of AMBN free radicalinitiator were dissolved in a solvent mixture consisting of 130.08 g ofwater, 44.22 g of methyl ethyl ketone (MEK), and 85.83 g of isopropylalcohol (IPA). The reaction mixture was purged with nitrogen capped witha septum and kept in a preheated oil bath at 80° C. overnight. Thereaction mixture was then cooled and placed in a dialysis bag with MWCOof 3500 and dialyzed until the bag was fully swollen. The contents werethen evaporated to a concentration of 15.3 weight % solids. The weightaverage molecular weight (M_(w)) of the resulting Terpolymer C was52,700 as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer D from 3-Sulfopropyl MethacrylatePotassium Salt, Methacrylic Acid, and7-(2-Methacryloyloxyethoxy)-4-Methylcoumarin in a 10:70:20 Mol % Ratio

1.6 g of 3-Sulfopropyl methacrylate potassium salt, 3.91 g ofmethacrylic acid, and 3.75 g of7-(2-methacryloyloxyethoxy)-4-methylcoumarin were weighed out in a 250ml single neck round bottom flask and dissolved in a solvent mixture of28 g of water, 28 g of dimethylacetamide (DMA), and 28 g of isopropylalcohol. 0.46 g of AMBN free radical initiator was added and nitrogenwas bubbled through the solvent mixture for 30 minutes before heating inan oil bath at 80° C. for about 18 hours. The reaction mixture wascooled and diluted with water to form a clear solution. The reactionsolution was dialyzed for about 18 hours and then concentrated to a14.52 weight % solids solution that was suitable for coating. The weightaverage molecular weight (M_(w)) of the resulting Terpolymer D was90,800 as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer E from 3-Sulfopropyl MethacrylatePotassium Salt, Methacrylic Acid, and7-(2-Methacryloyloxyethoxy)-4-Methylcoumarin in a 10:70:20 Mol % Ratiowith Reduced Molecular Weight

1.6 g of 3-Sulfopropyl methacrylate potassium salt, 1.25 g ofmethacrylic acid, and 3.75 g of7-(2-methacryloyloxyethoxy)-4-methylcoumarin were weighed out in a 250ml single neck round bottom flask and dissolved in a solvent mixture of18 g of water, 35 g of dimethylacetamide (DMA), and 53 g of isopropylalcohol. 0.46 g of AMBN free radical initiator was added and nitrogenwas bubbled through the slurry for 30 minutes before heating in an oilbath at 80° C. for about 18 hours. The reaction mixture was cooled anddiluted with water to form a clear solution. The reaction solution wasthen dialyzed for about 18 hours and then concentrated to an 8.80 weight% solids solution that was suitable for coating. The weight averagemolecular weight (M_(w)) of the resulting Terpolymer E was 41,900 asdetermined by size exclusion chromatography (SEC).

Preparation of Inventive Copolymer F from2-Acrylamido-2-Methyl-1-Propanesulfonic Acid and 2-Cinnamoyl-EthylMethacrylate in an 80:20 Mol % Ratio

In a 100 ml single neck round bottom flask, 4.15 g of2-acrylamido-2-methyl-1-propanesulfonic acid, 1.30 g of2-cinnamoyl-ethyl methacrylate, and 0.054 g of AMBN free radicalinitiator were dissolved in a solvent mixture consisting of 10.29 g ofwater, 10.29 g of methyl ethyl ketone (MEK), and 10.29 g of isopropylalcohol (IPA). The reaction mixture was purged with nitrogen capped witha septum and kept in a preheated oil bath at 70° C. overnight. Thereaction mixture was then cooled and placed in a dialysis bag with MWCOof 3500 and dialyzed until the bag was fully swollen. The contents werethen evaporated to a concentration of 18.9 weight % solids. The weightaverage molecular weight (M_(w)) of the resulting Copolymer F was 26,100as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer G from2-Acrylamido-2-Methyl-1-Propanesulfonic Acid, Methacrylic Acid, and2-Cinnamoyl-Ethyl Methacrylate in a 50:30:20 Mol % Ratio

In a 100 ml single neck round bottom flask, 2.59 g of2-acrylamido-2-methyl-1-propanesulfonic acid, 0.65 g of methacrylicacid, 1.30 g of 2-cinnamoyl-ethyl methacrylate, and 0.045 g of AMBN freeradical initiator were dissolved in a solvent mixture consisting of 8.58g of water, 8.58 g of methyl ethyl ketone (MEK), and 8.58 g of isopropylalcohol (IPA). The reaction mixture was purged with nitrogen capped witha septum and kept in a preheated oil bath at 70° C. overnight. Thereaction mixture was then cooled and placed in a dialysis bag with MWCOof 3500 and dialyzed until the bag was fully swollen. The contents werethen evaporated to a concentration of 18.64 weight % solids. The weightaverage molecular weight (M_(w)) of the resulting Terpolymer G was62,200 as determined by size exclusion chromatography (SEC).

Preparation of Inventive Copolymer H from2-Acrylamido-2-Methyl-1-Propanesuflfonic Acid and7-(2-Methacryloyloxyethoxy)-4-Methylcoumarin in an 80:20 Mol % Ratio

In a 100 ml single neck round bottom flask, 6.15 g of2-acrylamido-2-methyl-1-propanesulfonic acid, 2.14 g of7-(2-methacryloyloxyethoxy)-4-methylcoumarin, and 0.080 g of AMBN freeradical initiator were dissolved in a solvent mixture consisting of 11 gof water, 11 g of methyl ethyl ketone (MEK), and 8.5 g of isopropylalcohol (IPA). The reaction mixture was purged with nitrogen capped witha septum and kept in a preheated oil bath at 65° C. overnight. Thereaction mixture was then cooled and placed in a dialysis bag with MWCOof 3500 and dialyzed until the bag was fully swollen. The contents werethen evaporated to a concentration of 15.68 weight % solids. The weightaverage molecular weight (M_(w)) of the resulting Copolymer H was 48,900as determined by size exclusion chromatography (SEC).

Preparation of Inventive Terpolymer I from2-Acrylamido-2-Methyl-1-Propanesulfonic Acid, Methacrylic Acid, and7-(2-Methacryloyloxyethoxy)-4-Methylcoumarin in a 50:30:20 Mol % Ratio

In a 250 ml single neck round bottom flask, 7.15 g of2-acrylamido-2-methyl-1-propanesulfonic acid, 1.78 g of methacrylicacid, 3.98 g of 7-(2-Methacryloyloxyethoxy)-4-methylcoumarin, and 0.65 gof AMBN free radical initiator were dissolved in a solvent mixtureconsisting of 38 g of water, 38 g of methyl ethyl ketone (MEK), and 38 gof isopropyl alcohol (IPA). The reaction mixture was purged withnitrogen capped with a septum and kept in a preheated oil bath at 80° C.overnight. The reaction mixture was then cooled and placed in a dialysisbag with MWCO of 3500 and dialyzed until the bag was fully swollen. Thecontents were then evaporated to a concentration of 13.34 weight %solids. The weight average molecular weight (M_(w)) of the resultingTerpolymer I was 34,400 as determined by size exclusion chromatography(SEC).

Preparation of Comparative Copolymer J from 3-Sulfopropyl MethacrylatePotassium Salt and Methacrylic Acid in a 50:50 Mol % Ratio

In a 250 ml single neck round bottom flask, 8.0 g of 3-sulfopropylmethacrylate potassium salt was dissolved in 49 g of distilled water.Then 2.80 g of methacrylic acid was added along with 49 g of isopropylalcohol and 0.22 g of AMBN free radical initiator. The reaction mixturewas purged with nitrogen, capped with a septum and kept in a preheatedoil bath at 70° C. overnight. The reaction mixture was then cooled,diluted with water and placed in a dialysis bag with MWCO of 3500 anddialyzed until the bag was fully swollen. The contents were thenevaporated to a concentration of 12.57 weight % solids. The weightaverage molecular weight (M_(w)) of the resulting comparative CopolymerJ was 85,000 as determined by size exclusion chromatography (SEC).

General Preparation of Metal Nano-Particle UV-Crosslinkable PolymerComplex

Into a high density polyethylene bottle with magnetic stirring, thefollowing components were added in order: a quantity of an inventive injettable and UV-crosslinkable composition described above to provide 10weight % of reactive polymer in the final solution, along with anyadditional water required to adjust the final reaction concentration. Aquantity of 2 molar silver nitrate solution adequate to complex 75% ofthe available acid monomer units in the reactive polymer was then addeddropwise with good stirring. This was followed by the addition of a 4weight % solution of dimethyl amine borane (DMAB) such that the molarratio of silver ion to DMAB was about 9:1. The resulting solution wasthen placed in a dialysis tube with a molecular weight cut-off of 3500for about 24 hours. The solution was then concentrated to 10 to 15weight % total solids.

Preparation of Ink Jettable and UV-Curable Compositions

General Ink Jettable and UV-Curable Composition Preparation:

Into an approximately 60 ml high density polyethylene bottle equippedwith magnetic stirring, the following components were added in order: areactive polymer, about 50 to 90% of the makeup water, a humectant, asurfactant, any additional optional polymers such as a water-solublepolyurethane, and optionally about 0.02 weight % of a biocide such asKordek MLX. While stirring, a 2 molar solution of sodium hydroxide wasused to adjust the pH to 7.5+/−0.2 and any final makeup water was thenadded to adjust the total solids to aim. Pigment dispersions, dyes, orpH sensitive polymers were added after the pH was adjusted as describedabove. A final pH adjustment can be done after all components are added.The resulting ink jettable and UV-curable composition was stirred forapproximately 30 minutes and filtered with a 1.0 um disk filter. SeeTABLE I below for the components of the inventive ink jettable andUV-curable compositions 1-15.

TABLE I Ink Jettable and UV-curable Weight % UV- Weight % Weight %Composition Curable Polymer Humectant Surfactant Inventive 1 4%Terpolymer A 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 2 4%Terpolymer B 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 3 2%Terpolymer C 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 4 2%Terpolymer D 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 5 2%Terpolymer E 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 6 4%Copolymer F 10% 2- 0.5% Tergitol ® Pyrrolidinone 15-S-9 Inventive 7 4%Terpolymer G 10% 2- 0.5% Tergitol ® Pyrrolidinone 15-S-9 Inventive 8 2%Copolymer H 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 9 2%Terpolymer I 10% Ethylene 0.5% Tergitol ® glycol 15-S-9 Inventive 102.6% Terpolymer 10% Ethylene 0.5% Tergitol ® A Silver glycol 15-S-9Nanoparticle Complex Inventive 11 2.6% Terpolymer 10% Ethylene 0.5%Tergitol ® C Silver glycol 15-S-9 Nanoparticle Complex Inventive 12 2%Terpolymer C None 0.5% Tergitol ® 15-S-9 Inventive 13 2% Terpolymer C10% Ethylene None glycol Inventive 14 2% Terpolymer C None NoneInventive 15 8% Terpolymer A 10% Ethylene 0.5% Tergitol ® glycol 15-S-9

Basic ink jetting performance in a thermal print head was evaluatedusing an ink jetting fixture with a laser drop detector that was capableof determining the drop position after the ejection pulse and therebythe drop velocity as a function of ink ejection parameter such asvoltage, firing frequency, latency times, and total number of ejectionsfor each nozzle can be determined if required.

Jetting Performance of Ink Jettable and UV-Curable Compositions:

TABLE II Ink Jettable % Velocity and UV- Drop Velocity change of 1^(st)% Velocity curable velocity at COV at Frequency drop after 20 sec changeafter 10⁷ Composition 12 kHz 12 kHz limit kHz hold ejections Inventive 116 m/sec 0.5%   24 −9% +16% Inventive 2 19 m/sec 1.3%   19 −17% +7%Inventive 3 17 m/sec 2% 24 −9% +1% Inventive 4 17 m/sec 0.6%   24 −14%+12% Inventive 5 17 m/sec 1.7%   24 −47% −4% Inventive 6 17 m/sec 1% 19N/A N/A Inventive 7 17 m/sec 2% 12 N/A N/A Inventive 8 19 m/sec 1% 19N/A N/A Inventive 9 13 m/sec 2% 16 0% −12% Inventive 10 19 m/sec 2.5%  18 −28% −75% Inventive 11 18 m/sec 5% 18 −13% −65% Inventive 12 17 m/sec5% 22 −26% 0% Inventive 13 15 m/sec 3% 24 0% +7% Inventive 14 15 m/sec2% 24 0% +17%

The data in Table II show that ink jettable and UV-curable compositionsprepared according to the present invention using reactive polymersdescribed above and silver nanoparticle-polymer complexes can be ejectedfrom a thermal print head with high drop velocities and low dropvelocity variation at firing frequencies in excess of 20 kHz. The dataalso show adequate latency performance to allow printing with normalnozzle maintenance procedures. Moreover, the data show a drop invelocity change over 10 million ejections of less than about 20% forinks prepared without preformed metal nanoparticles indicating that theydo not damage the print head and would provide reliable jettingperformance. Metal-containing compositions prepared with a metalnano-particle complex showed higher velocity loss over the 10 millionejection cycle, but this could likely be improved through modificationsof the metal nanoparticle formation process such as longer dialysis toremove salts and ink formulation optimization. Inventive ink jettableand UV-curable compositions L, M, and N showed that both the humectantand the surfactant are optional and excellent jetting performance can beobtained without these addenda. This is likely due to the fact that thereactive polymers used in these examples have intrinsic surfactant andhumectant properties.

Preparation of Ink Jetted Prints (Patterns)

Inventive ink jettable and UV-curable Compositions A, B, C, D, J, K, andO were used to fill ink cartridges compatible with a Kodak® AIO desktopprinter having a thermal print head. Various short-circuit patterns withlines ranging from 0.25 mm to 1.0 mm in width were printed onto asupporting surface of a poly(ethylene terephthalate) (PET) support thathad been pre-coated with a glycidyl methacrylate-n-butyl methacrylatecopolymer layer. Each ink jet printed image was exposed to broadband UVradiation to crosslink (cure) the printed composition, and then eachcured image was electrolessly plated with copper as described below.

Electroless Copper Plating of Inkjet Printed Patterns: Preparation ofthe Electroless Copper Plating Bath

The following components were dissolved in a glass container that hadbeen cleaned with concentrated nitric acid followed by a thorough rinsewith distilled water to eliminate any trace of metal on the glass: 1.8 gof copper (II) sulfate pentahydrate, 6.25 g of tetrasodium EDTA(ethylenediaminetetraacetic acid) tetrahydrate, 0.005 g of potassiumferrocyanide trihydrate, 2.25 g of 37 weight % formaldehyde solution, 80g of distilled water, and about 2 to 3 g of a 45 weight % sodiumhydroxide solution to adjust the pH to 12.8.

Electroless Plating of Inkjet Patterns from Ink Jettable and UV-CurableCompositions without Pre-Formed Metal Nanoparticles:

The inkjet printed images of the short-circuit patterns described abovewere exposed to a 1000 W broadband UV source with a 350-450 nm dichroicmirror for an exposure times ranging from 0 (unexposed) to 240 seconds,then immersed in an agitated distilled water bath for 2 minutes toremove any non-cured polymer. The non-exposed pattern was completelydissolved as would be expected. The patterns receiving about 15 or moreseconds of UV exposure remained intact on the substrate although longerexposure times were required for thicker or higher % reactive polymercompositions. The wet patterns were then immersed in a 0.4 molar silvernitrate solution for 60 seconds and then washed in a distilled waterbath to remove any uncomplexed silver ion. The patterns were thenimmersed in a 1 weight % dimethylamine borane (DMAB) bath for 30 secondsto reduce the complexed silver ions and to form complexed silvernano-particles suitable for catalyzing the electroless copper plating.After using the DMAB bath, the reduced printed patterns were againwashed thoroughly in distilled water and then immersed in the agitatedelectroless copper plating bath described above for 10 minutes. A highlyconductive copper film was formed on the ink jet printed and UV-curedpatterns, allowing the short-circuit pattern to function and showconductivity if any of the fine copper wires formed in the pattern arecrossed by a conductive material.

Inventive Copper Electroless Plating of Inkjet Patterns Using aMetal-Containing Composition:

The ink jetted prints made using Inventive ink jettable and UV-curablecompositions J and K were exposed to a 1000 W broadband UV source with a350-450 nm dichroic mirror for exposure times ranging from 60 to 480seconds, then immersed in an agitated distilled water bath for 2 minutesto remove any non-cured reactive polymer. The resultingsilver-containing patterns were then immersed in the agitatedelectroless copper plating bath described above for 7 minutes. A highlyconductive copper pattern was formed on the silver-containing patterns,allowing the short-circuit pattern to function and showing conductivityif any of the fine copper wires formed in the pattern were crossed by aconductive material.

Inventive Ink Jettable and UV-Curable Composition Containing a Pigmentand Electroless Plating of Inkjet Printed Patterns:

An ink jettable and UV-curable composition was prepared according to thepresent invention as described above and containing 4 weight % ofInventive Terpolymer A, 10 weight % of ethylene glycol humectant, and0.5 weight % of Tergitol 15-S-9 surfactant. After adjusting the pH to7.5+/−0.2, 0.5 weight % of an aqueous cyan pigment dispersion was added.This cyan pigment dispersion contained C.I. Pigment Blue 15:3 (CAS147-14-8, also known as Phthalocyanine blue BGS) dispersed with aterpolymer dispersant derived from 37 weight % of benzyl methacrylate,30 weight % of n-octadecyl methacrylate, and 33 weight % of methacrylicacid (with 85% of the acid groups neutralized with potassium hydroxide).

The resulting silver-containing composition was loaded into an inkcartridge and printed using a thermal print-head desktop inkjet printeras described above. Electrode patterns having various line widths downto about 0.25 mm where printed, and exposed for 60 seconds to a 1000 Wbroadband UV source with a 350-450 nm dichroic mirror to cause curing ofthe reactive polymer (Inventive Terpolymer A). Following this UVexposure, the patterns were then immersed in an agitated distilled waterbath for 2 minutes, immersed for 1 minute in a 0.4 molar silver nitratebath, rinsed with distilled water, immersed for 30 seconds in a 0.68molar DMAB bath, rinsed with distilled water, and then immersed in theelectroless copper plating bath described above for 7 minutes. Highlyconductive, brilliant copper lines were formed where the cyanpigment-containing ink jettable and UV-curable composition had beenprinted and UV-cured.

Inventive Ink Jettable and UV-Curable Composition Containing a Pigmentand a Polyurethane and Electroless Plating of Ink Jet Printed Patterns:

An ink jettable and UV-curable composition was prepared according to thepresent invention as described above and containing 4 weight % ofInventive Terpolymer A, 10 weight % of ethylene glycol humectant, and0.5 weight % of Tergitol® 15-S-9 surfactant. After adjusting the pH to7.5+/−0.2, 0.5 weight % of the cyan pigment dispersion described abovewas added followed by the addition of 1 weight % of a water-solubleanionic polyether polyurethane with an acid number of 95 that had beenprepared using conventional methods from isophorone diisocyanate,Terathane 2000 polyether glycol, and 2,2-bis(hydroxymethyl)propionicacid. The anionic polyether polyurethane was 95% neutralized usingpotassium hydroxide before its addition to the formulation.

The ink jetting characteristics of this ink jettable and UV-curablecomposition were evaluated and compared to the ink jettable andUV-curable composition described above containing the cyan pigment butno anionic polyether polyurethane. The average drop velocity at a firingfrequency of 10 kHz improved from about 5 m/sec with a coefficient ofvariation of about 3% to 20 m/sec with a coefficient of variation ofabout 0.6%, thus showing that the additional polymer additive furtherimproved ink jetting characteristics.

Ink jetted patterns were prepared, UV-cured, processed to form complexedsilver nanoparticles, and electrolessly plated with copper as describedabove. Conductive copper metal lines were formed on the inkjet printedand UV-cured patterns.

Comparative Ink Jettable Composition:

An ink jettable composition outside of the present invention wasprepared as described above to contain 4 weight % of ComparativeCopolymer J, weight % of ethylene glycol humectant, 0.5 weight % ofTergitolS 15-S-9 surfactant. The pH was adjusted to 7.5+/−0.2. The inkjetting characteristics were evaluated using a laser drop detectionfixture. The average drop velocity at 10 kHz firing frequency wasmeasured at 10 m/sec with a coefficient of variation of 2.6%. ThisComparative silver metal-containing ink jettable composition was loadedinto an ink cartridge and ink jet printed using a thermal print-headdesktop inkjet printer as described above. Electrode patterns with linevarious line widths down to about 0.25 mm where ink jet printed, exposedwith a 1000 W broadband UV source with a 350-450 nm dichroic mirror fortimes ranging from 60 to 480 seconds.

Following the UV exposure, the printed patterns were then immersed in anagitated distilled water bath for 2 minutes, immersed for 1 minute in a0.4 molar silver nitrate bath, rinsed with distilled water, immersed for30 seconds in a 0.68 molar DMAB bath, rinsed with distilled water, andthen immersed in the electroless copper plating bath described above for7 minutes. No copper plating or conductive copper lines were formedbecause the printed patterns of the ink jettable composition washed offof the support because there was no pendant photocycloaddition groupspresent in the polymer to form crosslinks upon exposure to ultravioletlight. The ink jettable composition was not UV-curable.

Invention Nickel Electroless Plating of Ink Jet Printed PatternsCatalyzed with Palladium Nanoparticles:

Preparation of a Nickel Electroless Plating Bath

The following components were dissolved in a glass container that hadbeen cleaned with concentrated nitric acid followed by a thorough rinsewith distilled water to eliminate any trace of metal on the glass: 0.66g of nickel (II) nitrate hexahydrate, 5.62 g of 85 weight % of lacticacid, 2.36 g of glacial acetic acid, 0.446 g of propionic acid, 0.375 gof a 100 ppm solution of thiourea in methanol, 4.725 g of 14.3 molarammonium hydroxide solution, 130.4 g of distilled water, and 1.965 g ofsodium hypophosphite hydrate (assumed 95 weight % sodium hypophosphite)that was added immediately before use. The temperature of the resultingnickel electroless plating bath was adjusted to 55° C.

An ink jettable and UV-curable composition of the present invention wasprepared as described above to contain 4 weight % of InventiveTerpolymer A, 10 weight % of ethylene glycol humectant, 0.5 weight % ofTergitole 15-S-9 surfactant, and the pH was adjusted to 7.5+/−0.2. Theresulting ink jettable and UV-curable composition was loaded into an inkcartridge and ink jet printed using a thermal print-head desktop inkjetprinter as described above. An electrode pattern with line widths ofabout 0.5 mm was printed and exposed for 120 seconds with a 1000 Wbroadband UV source with a 350-450 nm dichroic mirror.

Following the UV exposure, the UV-cured patterns were then immersed inan agitated distilled water bath for 2 minutes, and immersed for 5minutes in a bath of 0.001 molar palladium chloride dissolved in a 1:1mixture of water and acetonitrile to form a reducible palladium metalcomplex in the inkjet printed pattern. The pattern was then rinsed for30 seconds in distilled water, immersed for 2 minutes in a 0.68 molarDMAB bath to reduce the palladium ions and to form a palladiumnanoparticle complex in the UV-cured pattern. This was followed by adistilled water rinse, and immersion in the electroless nickel platingbath described above for 10 minutes. Conductive grey nickel metal wasformed on the UV-cured pattern.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention.

1. An ink jettable and UV-curable composition comprising: a reactivepolymer comprising: (a1) at least 20 mol % of recurring units comprisingpendant metal complexing water-solubilizing groups, (b) at least 5 mol %of recurring units comprising a pendant group capable of crosslinkingvia [2+2] photocycloaddition, and optionally (c) at least 1 mol % ofrecurring units comprising a pendant amide, hydroxyl, or lactam group,or a pendant precursor moiety for the pendant amide, hydroxyl, or lactamgroup, all amounts based on the total recurring units in the reactivepolymer; and optionally, one or more of the following components: ahumectant, a dye or pigment colorant, an anionic or nonionic surfactant,a water-soluble or water-dispersible acrylic polymer, and awater-soluble or water-dispersible polyurethane.
 2. The ink jettable andUV-curable composition of claim 1, wherein the reactive polymercomprises at least 40 mol % of the (a1) recurring units comprisingsulfonic acid or sulfonate groups, based on the total recurring units inthe reactive polymer.
 3. The ink jettable and UV-curable composition ofclaim 1, wherein the reactive polymer comprises at least 5 mol % and upto and including 50 mol % of the (b) recurring units, based on the totalrecurring units in the reactive polymer.
 4. The ink jettable andUV-curable composition of claim 1, wherein the reactive polymercomprises at least 1 mole % and up to and including 55 mol % of (c)recurring units comprising pendant hydroxyl, amide, or carboxylic acidgroups, based on the total recurring units in the reactive polymer. 5.The ink jettable and UV-curable composition of claim 1, wherein the (b)recurring units comprise: (i) a photosensitive —C(═O)—CR═CR¹—Y groupwherein R and R¹ are independently hydrogen or an alkyl group having 1to 7 carbon atoms, a 5- to 6-membered cycloalkyl group, an alkoxy grouphaving 1 to 7 carbon atoms, a phenyl group, or a phenoxy group, and Y isan aryl or heteroaryl group; (ii) a photosensitive, non-aromaticunsaturated carbocyclic group; (iii) a photosensitive, aromatic ornon-aromatic heterocyclic group comprising a carbon-carbon double bondthat is conjugated with an electron withdrawing group; (iv) aphotosensitive non-aromatic unsaturated heterocyclic group comprisingone or more amide groups that are conjugated with a carbon-carbon doublebond, which photosensitive non-aromatic unsaturated heterocyclic groupis linked to the water-soluble backbone at an amide nitrogen atom; or(v) a photosensitive substituted or unsubstituted 1,2-diarylethylenegroup.
 6. The ink jettable and UV-curable composition of claim 1,further comprising a humectant that is chosen from at least one of thefollowing groups of compounds: (1) polyhydric alcohols; (2)polyoxygenated polyols and their derivatives; (3) sulfur-containingpolyol compounds; (4) cyclic lactams; and (5) cyclic ureas.
 7. The inkjettable and UV-curable composition of claim 1, further comprising apigment colorant.
 8. The ink jettable and UV-curable composition ofclaim 1 further comprising a pigment colorant that has a median particlediameter of less than 150 nm and more likely less than 100 nm, in anamount of at least 0.1 weight % and up to and including 30 weight %,based on the total weight of the ink jettable and UV-curablecomposition.
 9. The ink jettable and UV-curable composition of claim 1,further comprising a nonionic surfactant.
 10. The ink jettable andUV-curable composition of claim 1, further comprising a water-soluble orwater-dispersible polyurethane.
 11. The ink jettable and UV-curablecomposition of claim 1 having a viscosity of less than 3 centipoise asmeasured at 25° C.
 12. The ink jettable and UV-curable composition ofclaim 1, further comprising a photosensitizer.
 13. An ink jettable andUV-curable composition comprising: a complex of reducible metal ions ormetal nanoparticles with a reactive polymer, the reactive polymercomprising: (a2) at least 5 mol % of recurring units comprising pendantsulfonate groups, (b) at least 5 mol % of recurring units comprising apendant group capable of crosslinking via [2+2] photocycloaddition, andoptionally (c) at least 1 mol % of recurring units comprising a pendantamide, hydroxyl, lactam group, carboxylic acid, phosphonic acid group ora pendant precursor moiety for the pendant amide, hydroxyl, lactam,carboxylic acid, or phosphonic acid group, all amounts based on thetotal recurring units in the reactive polymer; and optionally, one ormore of the following components: a humectant, a dye or pigmentcolorant, an anionic or nonionic surfactant, a water-soluble orwater-dispersible acrylic polymer, and a water-soluble orwater-dispersible polyurethane.
 14. The ink jettable and UV-curablecomposition of claim 13 further comprising a pigment colorant that has amedian particle diameter of less than 150 nm and more likely less than100 nm, in an amount of at least 0.1 weight % and up to and including 30weight %, based on the total weight of the ink jettable and UV-curablecomposition.
 15. The ink jettable and UV-curable composition of claim 13that comprises a complex of reducible silver ions or silvernanoparticles with the reactive polymer.
 16. The ink jettable andUV-curable composition of claim 13, comprising a complex of silvernanoparticles with the reactive polymer, wherein the silvernanoparticles have an average diameter of at least 2 nm and up to andincluding 500 nm.
 17. The ink jettable and UV-curable composition ofclaim 13, comprising a complex of silver nanoparticles with the reactivepolymer, wherein the silver nanoparticles have an aspect ratio of lessthan
 2. 18. The ink jettable and UV-curable composition of claim 13,comprising a complex of silver nanoparticles with the reactive polymer,wherein the silver nanoparticles have an aspect ratio of greater than orequal to
 2. 19. The ink jettable and UV-curable composition of claim 13that comprises a complex of reducible palladium ions or palladiumnanoparticles with the reactive polymer.